diff --git a/libsrc/general/mpi_interface.hpp b/libsrc/general/mpi_interface.hpp
index bb173afb..a896338f 100644
--- a/libsrc/general/mpi_interface.hpp
+++ b/libsrc/general/mpi_interface.hpp
@@ -18,28 +18,11 @@ namespace netgen
   extern int id, ntasks;
   
 
-#ifndef PARALLEL
-
-  // enum { id = 0 };
-  // enum { ntasks = 0 };
-
-#else   // if PARALLEL
-
-
-// #include <mystdlib.h>
-// #include <myadt.hpp>
-//  #include <meshing.hpp>
-// #include "incvis.hpp"
-
-
-//#include "parallelfunc.hpp"
-  /*
-  extern MPI_Group MPI_HIGHORDER_WORLD;
-  extern MPI_Comm MPI_HIGHORDER_COMM;
-  */
-
-// namespace netgen
-// {
+#ifdef PARALLEL
+  
+  enum { MPI_TAG_CMD = 110 };
+  enum { MPI_TAG_MESH = 210 };
+  enum { MPI_TAG_VIS = 310 };
 
   template <class T>
   MPI_Datatype MyGetMPIType ( ) { cerr << "ERROR in GetMPIType() -- no type found" << endl;return 0;}
@@ -53,79 +36,79 @@ namespace netgen
   { return MPI_DOUBLE; }
 
 
-
+  
 
   // damit gehen auch echte Konstante ohne Adresse
-  inline void MyMPI_Send (int i, int dest)
+  inline void MyMPI_Send (int i, int dest, int tag)
   {
     int hi = i;
-    MPI_Send( &hi, 1, MPI_INT, dest, 1, MPI_COMM_WORLD);
+    MPI_Send( &hi, 1, MPI_INT, dest, tag, MPI_COMM_WORLD);
   }
 
-  inline void MyMPI_Recv (int & i, int src)
+  inline void MyMPI_Recv (int & i, int src, int tag)
   {
     MPI_Status status;
-    MPI_Recv( &i, 1, MPI_INT, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &i, 1, MPI_INT, src, tag, MPI_COMM_WORLD, &status);
   }
 
 
 
-  inline void MyMPI_Send (const string & s, int dest)
+  inline void MyMPI_Send (const string & s, int dest, int tag)
   {
-    MPI_Send( const_cast<char*> (s.c_str()), s.length(), MPI_CHAR, dest, 1, MPI_COMM_WORLD);
+    MPI_Send( const_cast<char*> (s.c_str()), s.length(), MPI_CHAR, dest, tag, MPI_COMM_WORLD);
   }
 
-  inline void MyMPI_Recv (string & s, int src)
+  inline void MyMPI_Recv (string & s, int src, int tag)
   {
     MPI_Status status;
     int len;
-    MPI_Probe (src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Probe (src, tag, MPI_COMM_WORLD, &status);
     MPI_Get_count (&status, MPI_CHAR, &len);
     s.assign (len, ' ');
-    MPI_Recv( &s[0], len, MPI_CHAR, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &s[0], len, MPI_CHAR, src, tag, MPI_COMM_WORLD, &status);
   }
 
  
 
 
   template <class T, int BASE>
-  inline void MyMPI_Send (FlatArray<T, BASE> s, int dest)
+  inline void MyMPI_Send (FlatArray<T, BASE> s, int dest, int tag)
   {
-    MPI_Send( &s.First(), s.Size(), MyGetMPIType<T>(), dest, 1, MPI_COMM_WORLD);
+    MPI_Send( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD);
   }
 
   template <class T, int BASE>
-  inline void MyMPI_Recv ( FlatArray<T, BASE> s, int src)
+  inline void MyMPI_Recv ( FlatArray<T, BASE> s, int src, int tag)
   {
     MPI_Status status;
-    MPI_Recv( &s.First(), s.Size(), MyGetMPIType<T>(), src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &s.First(), s.Size(), MyGetMPIType<T>(), src, tag, MPI_COMM_WORLD, &status);
   }
 
   template <class T, int BASE>
-  inline void MyMPI_Recv ( Array <T, BASE> & s, int src)
+  inline void MyMPI_Recv ( Array <T, BASE> & s, int src, int tag)
   {
     MPI_Status status;
     int len;
-    MPI_Probe (src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Probe (src, tag, MPI_COMM_WORLD, &status);
     MPI_Get_count (&status, MyGetMPIType<T>(), &len);
 
     s.SetSize (len);
-    MPI_Recv( &s.First(), len, MyGetMPIType<T>(), src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &s.First(), len, MyGetMPIType<T>(), src, tag, MPI_COMM_WORLD, &status);
   }
 
   template <class T, int BASE>
-  inline int MyMPI_Recv ( Array <T, BASE> & s)
+  inline int MyMPI_Recv ( Array <T, BASE> & s, int tag)
   {
     MPI_Status status;
     int len;
-    MPI_Probe (MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Probe (MPI_ANY_SOURCE, tag, MPI_COMM_WORLD, &status);
 
     int src = status.MPI_SOURCE;
 
     MPI_Get_count (&status, MyGetMPIType<T>(), &len);
 
     s.SetSize (len);
-    MPI_Recv( &s.First(), len, MyGetMPIType<T>(), src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &s.First(), len, MyGetMPIType<T>(), src, tag, MPI_COMM_WORLD, &status);
 
     return src;
   }
@@ -133,18 +116,19 @@ namespace netgen
 
 
   template <class T, int BASE>
-  inline void MyMPI_ISend (FlatArray<T, BASE> s, int dest, MPI_Request & request)
+  inline void MyMPI_ISend (FlatArray<T, BASE> s, int dest, int tag, MPI_Request & request)
   {
-    MPI_Isend( &s.First(), s.Size(), MyGetMPIType<T>(), dest, 1, MPI_COMM_WORLD, & request);
+    MPI_Isend( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD, & request);
   }
 
 
   template <class T, int BASE>
-  inline void MyMPI_IRecv (FlatArray<T, BASE> s, int dest, MPI_Request & request)
+  inline void MyMPI_IRecv (FlatArray<T, BASE> s, int dest, int tag, MPI_Request & request)
   {
-    MPI_Irecv( &s.First(), s.Size(), MyGetMPIType<T>(), dest, 1, MPI_COMM_WORLD, & request);
+    MPI_Irecv( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD, & request);
   }
 
+  /*
   template <class T, int BASE>
   inline void MyMPI_ISendTag (FlatArray<T, BASE> s, int dest, int tag,  MPI_Request & request)
   {
@@ -157,6 +141,8 @@ namespace netgen
   {
     MPI_Irecv( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD, & request);
   }
+  */
+
 
   /*
   template <class T, int BASE>
@@ -180,19 +166,19 @@ namespace netgen
   */
 
   template <class T, int BASE>
-  inline void MyMPI_ISend (FlatArray<T, BASE> s, int dest)
+  inline void MyMPI_ISend (FlatArray<T, BASE> s, int dest, int tag)
   {
     MPI_Request request;
-    MPI_Isend( &s.First(), s.Size(), MyGetMPIType<T>(), dest, 1, MPI_COMM_WORLD, &request);
+    MPI_Isend( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD, &request);
     MPI_Request_free (&request);
   }
 
 
   template <class T, int BASE>
-  inline void MyMPI_IRecv (FlatArray<T, BASE> s, int dest)
+  inline void MyMPI_IRecv (FlatArray<T, BASE> s, int dest, int tag)
   {
     MPI_Request request;
-    MPI_Irecv( &s.First(), s.Size(), MyGetMPIType<T>(), dest, 1, MPI_COMM_WORLD, &request);
+    MPI_Irecv( &s.First(), s.Size(), MyGetMPIType<T>(), dest, tag, MPI_COMM_WORLD, &request);
     MPI_Request_free (&request);
   }
 
@@ -248,49 +234,42 @@ namespace netgen
 
 
 
-  inline void MyMPI_Send (  int *& s, int & len,  int dest)
+  inline void MyMPI_Send (  int *& s, int & len,  int dest, int tag)
   {
-     MPI_Send( &len, 1, MPI_INT, dest, 1, MPI_COMM_WORLD);
-     MPI_Send( s, len, MPI_INT, dest, 1, MPI_COMM_WORLD);
+     MPI_Send( &len, 1, MPI_INT, dest, tag, MPI_COMM_WORLD);
+     MPI_Send( s, len, MPI_INT, dest, tag, MPI_COMM_WORLD);
   }
 
 
-  inline void MyMPI_Recv ( int *& s, int & len, int src)
+  inline void MyMPI_Recv ( int *& s, int & len, int src, int tag)
   {
     MPI_Status status;
-    MPI_Recv( &len, 1, MPI_INT, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &len, 1, MPI_INT, src, tag, MPI_COMM_WORLD, &status);
     if ( s ) 
       delete [] s;
     s = new int [len];
-    MPI_Recv( s, len, MPI_INT, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( s, len, MPI_INT, src, tag, MPI_COMM_WORLD, &status);
   }
 
 
 
-  inline void MyMPI_Send ( double * s, int len,  int dest)
+  inline void MyMPI_Send ( double * s, int len,  int dest, int tag)
   {
-     MPI_Send( &len, 1, MPI_INT, dest, 1, MPI_COMM_WORLD);
-     MPI_Send( s, len, MPI_DOUBLE, dest, 1, MPI_COMM_WORLD);
+     MPI_Send( &len, 1, MPI_INT, dest, tag, MPI_COMM_WORLD);
+     MPI_Send( s, len, MPI_DOUBLE, dest, tag, MPI_COMM_WORLD);
   }
 
 
-  inline void MyMPI_Recv ( double *& s, int & len, int src)
+  inline void MyMPI_Recv ( double *& s, int & len, int src, int tag)
   {
     MPI_Status status;
-    MPI_Recv( &len, 1, MPI_INT, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( &len, 1, MPI_INT, src, tag, MPI_COMM_WORLD, &status);
     if ( s )
       delete [] s;
     s = new double [len];
-    MPI_Recv( s, len, MPI_DOUBLE, src, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
+    MPI_Recv( s, len, MPI_DOUBLE, src, tag, MPI_COMM_WORLD, &status);
   }
 
-
-// #include "parallelmesh.hpp"
-// #include "paralleltop.hpp"
-// #include "parallelinterface.hpp"
-
-// }
-
 #endif // PARALLEL
 
 }
diff --git a/libsrc/interface/nginterface.cpp b/libsrc/interface/nginterface.cpp
index 41b1d962..7851ecce 100644
--- a/libsrc/interface/nginterface.cpp
+++ b/libsrc/interface/nginterface.cpp
@@ -27,7 +27,7 @@
   static pthread_t meshingthread;
   void RunParallel ( void * (*fun)(void *), void * in)
   {
-    if (netgen::mparam.parthread)
+    if (netgen::mparam.parthread && (ntasks == 1) )
      {
 	     pthread_attr_t attr;
 	     pthread_attr_init (&attr);
@@ -37,7 +37,7 @@
 	     pthread_create (&meshingthread, &attr, fun, in);
      }
      else
-     fun (in);
+       fun (in);
   }
 
 #else // Using MS VC++ Standard / Enterprise / Professional edition
@@ -66,11 +66,11 @@
 #else  // For #ifdef _MSC_VER
 
 // #include <pthread.h>
-
+ 
   static pthread_t meshingthread;
   void RunParallel ( void * (*fun)(void *), void * in)
   {
-    if (netgen::mparam.parthread)
+    if (netgen::mparam.parthread && (netgen::ntasks == 1))
       {
 	pthread_attr_t attr;
 	pthread_attr_init (&attr);
diff --git a/libsrc/meshing/parallelmesh.cpp b/libsrc/meshing/parallelmesh.cpp
index 57ab3571..242af4cb 100644
--- a/libsrc/meshing/parallelmesh.cpp
+++ b/libsrc/meshing/parallelmesh.cpp
@@ -113,7 +113,7 @@ namespace netgen
     // int ve = 0;
     while (!endmesh)
       {
-	MyMPI_Recv (st, 0);
+	MyMPI_Recv (st, 0, MPI_TAG_MESH);
 
 	// receive vertices
         if (st == "vertex")
@@ -121,7 +121,7 @@ namespace netgen
 	    NgProfiler::RegionTimer reg(timer_pts);
 
 	    Array<int> verts;
-	    MyMPI_Recv (verts, 0);
+	    MyMPI_Recv (verts, 0, MPI_TAG_MESH);
 
 	    int numvert = verts.Size();
 	    paralleltop -> SetNV (numvert);
@@ -140,10 +140,10 @@ namespace netgen
 
 	    MPI_Datatype mptype = MeshPoint::MyGetMPIType();
 	    MPI_Status status;
-	    MPI_Recv( &points[1], numvert, mptype, 0, 33, MPI_COMM_WORLD, &status);
+	    MPI_Recv( &points[1], numvert, mptype, 0, MPI_TAG_MESH, MPI_COMM_WORLD, &status);
 
 	    Array<int> dist_pnums;
-	    MyMPI_Recv (dist_pnums, 0);
+	    MyMPI_Recv (dist_pnums, 0, MPI_TAG_MESH);
 
 	    for (int hi = 0; hi < dist_pnums.Size(); hi += 3)
 	      paralleltop ->
@@ -161,7 +161,7 @@ namespace netgen
 	    Element el;
 
             Array<int> elarray;
-            MyMPI_Recv (elarray, 0);
+            MyMPI_Recv (elarray, 0, MPI_TAG_MESH);
 
 	    for (int ind = 0, elnum = 1; ind < elarray.Size(); elnum++)
 	      {
@@ -181,7 +181,7 @@ namespace netgen
 	if (strcmp (st.c_str(), "facedescriptor") == 0)
 	  {
 	    Array<double> doublebuf;
-	    MyMPI_Recv( doublebuf, 0 );
+	    MyMPI_Recv( doublebuf, 0, MPI_TAG_MESH );
 	    int faceind = AddFaceDescriptor (FaceDescriptor(int(doublebuf[0]), int(doublebuf[1]), int(doublebuf[2]), 0));
 	    GetFaceDescriptor(faceind).SetBCProperty (int(doublebuf[3]));
 	    GetFaceDescriptor(faceind).domin_singular = doublebuf[4];
@@ -205,7 +205,7 @@ namespace netgen
 	    // tri.pnum
 	    // tri.geominfopi.trignum
 	    int nlocsel;
-	    MyMPI_Recv ( selbuf, bufsize, 0);
+	    MyMPI_Recv ( selbuf, bufsize, 0, MPI_TAG_MESH);
 	    int ii= 0;
 	    int sel = 0;
 
@@ -249,7 +249,7 @@ namespace netgen
 
 	    double * segmbuf = 0;
 	    int bufsize;
-	    MyMPI_Recv ( segmbuf, bufsize, 0);
+	    MyMPI_Recv ( segmbuf, bufsize, 0, MPI_TAG_MESH);
 	    Segment seg;
 	    int globsegi;
 	    int ii = 0;
@@ -365,7 +365,7 @@ namespace netgen
     // send partition
 
     for (int dest = 1; dest < ntasks; dest++)
-      MyMPI_Send ("mesh", dest);
+      MyMPI_Send ("mesh", dest, MPI_TAG_CMD);
     SendRecvMesh (); 
 
 
@@ -914,8 +914,8 @@ namespace netgen
       {
 	FlatArray<PointIndex> verts = verts_of_proc[dest];
 
-	MyMPI_Send ("vertex", dest);
-	MyMPI_ISend (verts, dest);
+	MyMPI_Send ("vertex", dest, MPI_TAG_MESH);
+	MyMPI_ISend (verts, dest, MPI_TAG_MESH);
 
 	MPI_Datatype mptype = MeshPoint::MyGetMPIType();
 
@@ -931,7 +931,7 @@ namespace netgen
 	MPI_Type_commit (&newtype);
 
 	MPI_Request request;
-	MPI_Isend( &points[0], 1, newtype, dest, 33, MPI_COMM_WORLD, &request);
+	MPI_Isend( &points[0], 1, newtype, dest, MPI_TAG_MESH, MPI_COMM_WORLD, &request);
 	MPI_Request_free (&request);
       }
 
@@ -964,7 +964,7 @@ namespace netgen
     
     for ( int dest = 1; dest < ntasks; dest ++ )
       {
-	MyMPI_ISend ( distpnums[dest], dest, sendrequest[dest] );
+	MyMPI_ISend ( distpnums[dest], dest, MPI_TAG_MESH, sendrequest[dest] );
 	MPI_Request_free (&sendrequest[dest]);
       }
 
@@ -1003,8 +1003,8 @@ namespace netgen
 
     for (int dest = 1; dest < ntasks; dest ++ )
       {
-	MyMPI_Send ( "volumeelements", dest);
-	MyMPI_ISend ( elementarrays[dest], dest, sendrequest[dest] );
+	MyMPI_Send ( "volumeelements", dest, MPI_TAG_MESH);
+	MyMPI_ISend ( elementarrays[dest], dest, MPI_TAG_MESH, sendrequest[dest] );
       }
 
 
@@ -1022,7 +1022,7 @@ namespace netgen
     for ( int dest = 1; dest < ntasks; dest++)
       for ( int fdi = 1; fdi <= mastermesh->GetNFD(); fdi++)
         {
-	  MyMPI_Send("facedescriptor", dest);
+	  MyMPI_Send("facedescriptor", dest, MPI_TAG_MESH);
 
           double6[0] = GetFaceDescriptor(fdi).SurfNr();
           double6[1] = GetFaceDescriptor(fdi).DomainIn();	
@@ -1031,7 +1031,7 @@ namespace netgen
 	  double6[4] = GetFaceDescriptor(fdi).domin_singular;
 	  double6[5] = GetFaceDescriptor(fdi).domout_singular;
 
-	  MyMPI_Send ( double6, dest);
+	  MyMPI_Send ( double6, dest, MPI_TAG_MESH);
         }
 
     endtime = clock();
@@ -1088,7 +1088,7 @@ namespace netgen
 
     for ( int dest = 1; dest < ntasks; dest++ )
       {
-	MyMPI_Send ( "surfaceelementsgi", dest);  
+	MyMPI_Send ( "surfaceelementsgi", dest, MPI_TAG_MESH);  
 	selbuf[dest][0] = nlocsel[dest];                  
       }    
 
@@ -1140,7 +1140,7 @@ namespace netgen
 
 
     for ( int dest = 1; dest < ntasks; dest++)
-      MyMPI_Send( selbuf[dest], bufsize[dest], dest);
+      MyMPI_Send( selbuf[dest], bufsize[dest], dest, MPI_TAG_MESH);
 
     for ( int dest = 0; dest < ntasks; dest++ )
       {
@@ -1157,7 +1157,7 @@ namespace netgen
 
     PrintMessage ( 3, "Sending Edge Segments");
     for ( int dest = 1; dest < ntasks; dest++ )
-      MyMPI_Send ( "edgesegmentsgi", dest);    
+      MyMPI_Send ( "edgesegmentsgi", dest, MPI_TAG_MESH);    
 
 
     Array <int> nlocseg(ntasks), segi(ntasks);
@@ -1242,7 +1242,7 @@ namespace netgen
 
     for ( int dest = 1; dest < ntasks; dest++)
       {
-	MyMPI_Send( segmbuf[dest], bufsize[dest], dest);
+	MyMPI_Send( segmbuf[dest], bufsize[dest], dest, MPI_TAG_MESH);
       }
     
     for ( int dest = 0; dest < ntasks; dest++ )
@@ -1260,7 +1260,7 @@ namespace netgen
 
 
     for ( int dest = 1; dest < ntasks; dest++ )
-      MyMPI_Send("endmesh", dest);
+      MyMPI_Send("endmesh", dest, MPI_TAG_MESH);
 
 
     for ( int dest = 1; dest < ntasks; dest ++ )
diff --git a/libsrc/meshing/paralleltop.cpp b/libsrc/meshing/paralleltop.cpp
index b9af1472..141ccb05 100644
--- a/libsrc/meshing/paralleltop.cpp
+++ b/libsrc/meshing/paralleltop.cpp
@@ -777,7 +777,7 @@ namespace netgen
 	MyMPI_Bcast ( sendarray );
       }
     else
-      MyMPI_ISend ( sendarray, 0, sendrequest );
+      MyMPI_ISend ( sendarray, 0, MPI_TAG_MESH, sendrequest );
 
 
     int nloops = (id == 0) ? ntasks-1 : 1;
@@ -787,7 +787,7 @@ namespace netgen
 
 	if (id == 0)
 	  {
-	    sender = MyMPI_Recv ( recvarray );
+	    sender = MyMPI_Recv ( recvarray, MPI_TAG_MESH );
 	    PrintMessage (4, "have received from ", sender);
 	  }
 	else
@@ -1481,7 +1481,7 @@ namespace netgen
 	(*sendarray)[1] = sendnfa;
 	(*sendarray)[2] = sendned;
 
-	MyMPI_Send (*sendarray, 0);
+	MyMPI_Send (*sendarray, 0, MPI_TAG_MESH);
 
 	delete sendarray;
       }
@@ -1492,7 +1492,7 @@ namespace netgen
 
 	for ( int sender = 1; sender < ntasks; sender++ )
 	  {
-	    MyMPI_Recv ( *recvarray, sender);
+	    MyMPI_Recv ( *recvarray, sender, MPI_TAG_MESH);
 
 	    int distnel = (*recvarray)[0];
 	    int distnfa = (*recvarray)[1];
@@ -1630,14 +1630,14 @@ namespace netgen
 	  for ( int dest = 1; dest < ntasks; dest ++ )
 	    if ( dest != id)
 	      {
-		MyMPI_Send ( *(elementonproc[dest]), dest);
+		MyMPI_Send ( *(elementonproc[dest]), dest, MPI_TAG_MESH);
 		elementonproc[dest] -> SetSize(0);
 	      }
 	
       
 	if ( id != sender )
 	  {
-	    MyMPI_Recv (*( recvelonproc[sender]), sender);
+	    MyMPI_Recv (*( recvelonproc[sender]), sender, MPI_TAG_MESH);
 	  }
       }
 
@@ -1694,14 +1694,14 @@ namespace netgen
 	  for ( int dest = 1; dest < ntasks; dest ++ )
 	    if ( dest != id)
 	      {
-		MyMPI_Send ( *(elementonproc[dest]), dest);
+		MyMPI_Send ( *(elementonproc[dest]), dest, MPI_TAG_MESH);
 		delete elementonproc[dest];
 	      }
 	
       
 	if ( id != sender )
 	  {
-	    MyMPI_Recv (*( recvelonproc[sender]), sender);
+	    MyMPI_Recv (*( recvelonproc[sender]), sender, MPI_TAG_MESH);
 	  }
       }
 
diff --git a/libsrc/visualization/mvdraw.cpp b/libsrc/visualization/mvdraw.cpp
index 3464c7a9..475a9a7e 100644
--- a/libsrc/visualization/mvdraw.cpp
+++ b/libsrc/visualization/mvdraw.cpp
@@ -768,23 +768,22 @@ namespace netgen
 
 	    Array<MPI_Request> request(ntasks);
 	    MPI_Status status;
-	    for ( int dest = 1; dest < ntasks; dest++ )
+	    for (int dest = 1; dest < ntasks; dest++)
 	      {
-		MyMPI_Send ("redraw", dest);
-		MyMPI_Send ("init", dest);
+		cout << "Initparallelgl, send to " << dest << endl;
+		MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+		MyMPI_Send ("init", dest, MPI_TAG_VIS);
 		
-		MyMPI_Send (displname, dest);
-		MyMPI_Send (int (drawable), dest);
-		MyMPI_Send (int (xid), dest);
+		MyMPI_Send (displname, dest, MPI_TAG_VIS);
+		MyMPI_Send (int (drawable), dest, MPI_TAG_VIS);
+		MyMPI_Send (int (xid), dest, MPI_TAG_VIS);
 
 		int hi;
-		MPI_Irecv( &hi, 1, MPI_INT, dest, MPI_ANY_TAG, MPI_COMM_WORLD, &request[dest]);
+		MPI_Irecv( &hi, 1, MPI_INT, dest, MPI_TAG_VIS, MPI_COMM_WORLD, &request[dest]);
 		// MyMPI_IRecv (hi, dest, request[dest]);
 	      } 
 	    for ( int dest = 1; dest < ntasks; dest++ )
-	      {
-		MPI_Wait(&request[dest], &status);
-	      }
+	      MPI_Wait(&request[dest], &status);
 	  }
       }
   }
@@ -798,8 +797,8 @@ namespace netgen
       {
 	for (int dest = 1; dest < ntasks; dest++)
 	  {
-	    MyMPI_Send ("redraw", dest);
-	    MyMPI_Send ("broadcast", dest);
+	    MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+	    MyMPI_Send ("broadcast", dest, MPI_TAG_VIS);
 	  }
       }
 
diff --git a/libsrc/visualization/vsmesh.cpp b/libsrc/visualization/vsmesh.cpp
index b27f4ebe..4569a252 100644
--- a/libsrc/visualization/vsmesh.cpp
+++ b/libsrc/visualization/vsmesh.cpp
@@ -903,12 +903,12 @@ namespace netgen
 
 	for ( int dest = 1; dest < ntasks; dest++ )
 	  {
-            MyMPI_Send ("redraw", dest);
-            MyMPI_Send ("filledlist", dest);
+            MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+            MyMPI_Send ("filledlist", dest, MPI_TAG_VIS);
 	  }
 	for ( int dest = 1; dest < ntasks; dest++ )
 	  {
-            MyMPI_Recv (par_filledlists[dest], dest);
+            MyMPI_Recv (par_filledlists[dest], dest, MPI_TAG_VIS);
             cout << "proc " << dest << " has drawn to list " << par_filledlists[dest] << endl;
 	  }
 
@@ -1323,7 +1323,7 @@ namespace netgen
 #ifdef PARALLELGL
     glFinish();
     if (id > 0)
-      MyMPI_Send (filledlist, 0);
+      MyMPI_Send (filledlist, 0, MPI_TAG_VIS);
 #endif
 
     // endtime = clock();
@@ -1346,11 +1346,11 @@ namespace netgen
 
 	for ( int dest = 1; dest < ntasks; dest++ )
 	  {
-            MyMPI_Send ("redraw", dest);
-            MyMPI_Send ("linelist", dest);
+            MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+            MyMPI_Send ("linelist", dest, MPI_TAG_VIS);
 	  }
 	for ( int dest = 1; dest < ntasks; dest++ )
-	  MyMPI_Recv (par_linelists[dest], dest);
+	  MyMPI_Recv (par_linelists[dest], dest, MPI_TAG_VIS);
 
 	if (linelist)
 	  glDeleteLists (linelist, 1);
@@ -1604,7 +1604,7 @@ namespace netgen
 #ifdef PARALLELGL
     glFinish();
     if (id > 0)
-      MyMPI_Send (linelist, 0);
+      MyMPI_Send (linelist, 0, MPI_TAG_VIS);
 #endif
   }
 
diff --git a/libsrc/visualization/vssolution.cpp b/libsrc/visualization/vssolution.cpp
index bb6cc938..6a8db2c5 100644
--- a/libsrc/visualization/vssolution.cpp
+++ b/libsrc/visualization/vssolution.cpp
@@ -996,11 +996,11 @@ namespace netgen
 
 	for ( int dest = 1; dest < ntasks; dest++ )
 	  {
-	    MyMPI_Send ("redraw", dest);
-	    MyMPI_Send ("solsurfellist", dest);
+	    MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+	    MyMPI_Send ("solsurfellist", dest, MPI_TAG_VIS);
 	  }
 	for ( int dest = 1; dest < ntasks; dest++ )
-	  MyMPI_Recv (par_surfellists[dest], dest);
+	  MyMPI_Recv (par_surfellists[dest], dest, MPI_TAG_VIS);
 
 	if (surfellist)
 	  glDeleteLists (surfellist, 1);
@@ -1317,7 +1317,7 @@ namespace netgen
 #ifdef PARALLELGL
     glFinish();
     if (id > 0)
-      MyMPI_Send (surfellist, 0);
+      MyMPI_Send (surfellist, 0, MPI_TAG_VIS);
 #endif
   }
 
@@ -3708,11 +3708,11 @@ namespace netgen
 
 	for ( int dest = 1; dest < ntasks; dest++ )
 	  {
-	    MyMPI_Send ("redraw", dest);
-	    MyMPI_Send ("clipplanetrigs", dest);
+	    MyMPI_Send ("redraw", dest, MPI_TAG_CMD);
+	    MyMPI_Send ("clipplanetrigs", dest, MPI_TAG_VIS);
 	  }
 	for ( int dest = 1; dest < ntasks; dest++ )
-	  MyMPI_Recv (parlists[dest], dest);
+	  MyMPI_Recv (parlists[dest], dest, MPI_TAG_VIS);
 
 	if (clipplanelist_scal)
 	  glDeleteLists (clipplanelist_scal, 1);
@@ -3856,7 +3856,7 @@ namespace netgen
 #ifdef PARALLELGL
     glFinish();
     if (id > 0)
-      MyMPI_Send (clipplanelist_scal, 0);
+      MyMPI_Send (clipplanelist_scal, 0, MPI_TAG_VIS);
 #endif
   }
 
diff --git a/ng/ngpkg.cpp b/ng/ngpkg.cpp
index 946e3579..14d01340 100644
--- a/ng/ngpkg.cpp
+++ b/ng/ngpkg.cpp
@@ -2999,7 +2999,7 @@ void PlayAnimFile(const char* name, int speed, int maxcnt)
 
 #ifdef PARALLEL
     for ( int dest = 1; dest < ntasks; dest++)
-      MyMPI_Send ( "end", dest );
+      MyMPI_Send ( "end", dest, MPI_TAG_CMD );
 #endif
 
     mesh.Reset (NULL);
diff --git a/ng/parallelfunc.cpp b/ng/parallelfunc.cpp
index a6bc859e..364af101 100644
--- a/ng/parallelfunc.cpp
+++ b/ng/parallelfunc.cpp
@@ -111,7 +111,7 @@ void ParallelRun()
 #pragma pomp inst begin (message)
 #endif
 
-      MyMPI_Recv ( message, 0 );
+      MyMPI_Recv ( message, 0, MPI_TAG_CMD );
 
 #ifdef SCALASCA
 #pragma pomp inst end (message)
@@ -224,7 +224,7 @@ void ParallelRun()
             // did not manage to get glXImportContextEXT working on Laptop (JS)
 
 	    string redraw_cmd;
-	    MyMPI_Recv (redraw_cmd, 0);
+	    MyMPI_Recv (redraw_cmd, 0, MPI_TAG_VIS);
 
 	    // PrintMessage (1, "Redraw - ", redraw_cmd);
                   
@@ -238,9 +238,9 @@ void ParallelRun()
 	    // if (!display)
 	    if (redraw_cmd == "init")
 	      {
-		MyMPI_Recv (displname, 0);
-		MyMPI_Recv (curDrawable, 0);
-		MyMPI_Recv (contextid, 0);
+		MyMPI_Recv (displname, 0, MPI_TAG_VIS);
+		MyMPI_Recv (curDrawable, 0, MPI_TAG_VIS);
+		MyMPI_Recv (contextid, 0, MPI_TAG_VIS);
 		
 		
 		display = XOpenDisplay (displname.c_str());
@@ -352,7 +352,7 @@ void ParallelRun()
 
 		// PrintMessage (1, "redraw - init complete");
 		int hi = id;
-		MyMPI_Send (hi, 0);
+		MyMPI_Send (hi, 0, MPI_TAG_VIS);
 	      }
 	    
 	    if (redraw_cmd == "broadcast")
diff --git a/nglib/nglib.cpp b/nglib/nglib.cpp
index 8a3b493b..ecde9c91 100644
--- a/nglib/nglib.cpp
+++ b/nglib/nglib.cpp
@@ -31,14 +31,17 @@ namespace netgen {
                                  MeshingParameters & mp);
 }
 
+namespace netgen
+{
+   int id, ntasks;
+}
+
 
 #ifdef PARALLEL
 #include <mpi.h>
 
 namespace netgen
 {
-   int id, ntasks;
-
    MPI_Group MPI_HIGHORDER_WORLD;
    MPI_Comm MPI_HIGHORDER_COMM;
 }