Index: /issm/trunk-jpl/src/c/modules/IoModelToConstraintsx/IoModelToConstraintsx.cpp
===================================================================
--- /issm/trunk-jpl/src/c/modules/IoModelToConstraintsx/IoModelToConstraintsx.cpp	(revision 17843)
+++ /issm/trunk-jpl/src/c/modules/IoModelToConstraintsx/IoModelToConstraintsx.cpp	(revision 17844)
@@ -44,4 +44,5 @@
 	bool *my_edges = NULL;
 	bool *my_faces = NULL;
+	bool *boundaryedge = NULL;
 
 	switch(finite_element){
@@ -74,4 +75,5 @@
 				FacesPartitioning(&my_faces,iomodel);
 			}
+			EdgeOnBoundaryFlags(&boundaryedge,iomodel);
 			break;
 		case P2xP4Enum:
@@ -106,5 +108,5 @@
 				}
 				for(i=0;i<iomodel->numberofedges;i++){
-					if(my_edges[i]){
+					if(my_edges[i] && boundaryedge[i]){
 						v1 = iomodel->edges[3*i+0]-1;
 						v2 = iomodel->edges[3*i+1]-1;
@@ -466,3 +468,4 @@
 	xDelete<bool>(my_edges);
 	xDelete<bool>(my_faces);
+	xDelete<bool>(boundaryedge);
 }
Index: /issm/trunk-jpl/src/c/modules/ModelProcessorx/CreateEdges.cpp
===================================================================
--- /issm/trunk-jpl/src/c/modules/ModelProcessorx/CreateEdges.cpp	(revision 17843)
+++ /issm/trunk-jpl/src/c/modules/ModelProcessorx/CreateEdges.cpp	(revision 17844)
@@ -144,23 +144,91 @@
 	iomodel->numberofedges             = nbe;
 }/*}}}*/
-void EdgeOnBoundaryFlags(IoModel* iomodel,bool** pflags){
-
-	/*Get faces and edges*/
+void EdgeOnBoundaryFlags(bool** pflags,IoModel* iomodel){/*{{{*/
+
+	/*Intermediaries*/
+	bool isv1,isv2;
+	int  facenbv,v1,v2;
+	int  id_edge,id_element,id_face;
+	int  elementnbe;
+
+	/*Mesh dependent variables*/
+	switch(iomodel->meshelementtype){
+		case TriaEnum:  elementnbe = 3; break;
+		case TetraEnum: elementnbe = 6; break;
+		case PentaEnum: elementnbe = 9; break;
+		default:        _error_("mesh dimension not supported yet");
+	}
+
+	/*Get edges and allocate output*/
 	if(!iomodel->edges) CreateEdges(iomodel);
-	if(!iomodel->faces) CreateFaces(iomodel);
-
-	/*Allocate output*/
-	bool* flags = xNew<bool>(iomodel->numberofedges);
-
-	/*Now, loop over the faces, whenever it is not connected to a second element, all edges are on boundary*/
-	for(int i=0;i<iomodel->numberoffaces;i++){
-
-		if(iomodel->faces[i*iomodel->facescols+4]==-1){
-
-			/*Get all edges for this face*/
-		}
+	bool* flags = xNewZeroInit<bool>(iomodel->numberofedges);
+
+	if(iomodel->domaindim==2){
+
+		/*Count how many times an edge is found in elementtoedgeconnectivity*/
+		int* counter = xNewZeroInit<int>(iomodel->numberofedges);
+		for(int i=0;i<iomodel->numberofelements;i++){
+			for(int j=0;j<elementnbe;j++){
+				counter[iomodel->elementtoedgeconnectivity[elementnbe*i+j]] += 1;
+			}
+		}
+
+		/*Now, loop over the egdes, whenever it is not connected to a second element, the edge is on boundary*/
+		for(int i=0;i<iomodel->numberofedges;i++){
+			if(counter[i]==1) flags[i]=true;
+		}
+
+		/*Clean up*/
+		xDelete<int>(counter);
+	}
+	else if(iomodel->domaindim==3){
+
+		/*Get faces*/
+		if(!iomodel->faces) CreateFaces(iomodel);
+
+		/*Now, loop over the faces, whenever it is not connected to a second element, all edges are on boundary*/
+		for(int id_face=0;id_face<iomodel->numberoffaces;id_face++){
+
+			if(iomodel->faces[id_face*iomodel->facescols+1]==-1){
+
+				/*The face is connected to the element e only*/
+				id_element = iomodel->faces[id_face*iomodel->facescols+0]-1;
+				facenbv    = iomodel->faces[id_face*iomodel->facescols+3];
+
+				/*Get all edges for this element*/
+				for(int edge = 0; edge<elementnbe; edge++){
+
+					id_edge     = iomodel->elementtoedgeconnectivity[elementnbe*id_element+edge];
+					v1          = iomodel->edges[id_edge*3+0];
+					v2          = iomodel->edges[id_edge*3+1];
+
+					/*Test if v1 is in the face*/
+					isv1=false;
+					for(int i=0;i<facenbv;i++){
+						if(iomodel->faces[id_face*iomodel->facescols+4+i] == v1){
+							isv1 = true; break;
+						}
+					}
+					if(!isv1) continue;
+
+					/*test if v2 is in the face*/
+					isv2=false;
+					for(int i=0;i<facenbv;i++){
+						if(iomodel->faces[id_face*iomodel->facescols+4+i] == v2){
+							isv2 = true; break;
+						}
+					}
+
+					/*If v1 and v2 are found, this edge is on boundary*/
+					if(isv2) flags[id_edge] = true;
+				}
+			}
+		}
+	}
+	else{
+		_error_("dimension not supported");
 	}
 
 	/*Clean up and return*/
 	*pflags = flags;
-}
+}/*}}}*/
Index: /issm/trunk-jpl/src/c/modules/ModelProcessorx/ModelProcessorx.h
===================================================================
--- /issm/trunk-jpl/src/c/modules/ModelProcessorx/ModelProcessorx.h	(revision 17843)
+++ /issm/trunk-jpl/src/c/modules/ModelProcessorx/ModelProcessorx.h	(revision 17844)
@@ -33,5 +33,5 @@
 void CreateFaces(IoModel* iomodel);
 void CreateFaces3d(IoModel* iomodel);
-void EdgeOnBoundaryFlags(IoModel* iomodel,bool** pflags);
+void EdgeOnBoundaryFlags(bool** pflags,IoModel* iomodel);
 
 /*Connectivity*/