diff -rupN gmsh-2.12.0-source/Mesh/meshGRegion.cpp gmsh-2.12.0-source-new/Mesh/meshGRegion.cpp
--- gmsh-2.12.0-source/Mesh/meshGRegion.cpp	2016-01-24 09:39:09.000000000 +0100
+++ gmsh-2.12.0-source-new/Mesh/meshGRegion.cpp	2016-03-06 11:50:14.241713400 +0100
@@ -459,7 +459,9 @@ bool CreateAnEmptyVolumeMesh(GRegion *gr
 	  (Msg::GetVerbosity() < 3) ? "Q" : (Msg::GetVerbosity() > 6) ? "V" : "",
           CTX::instance()->mesh.toleranceInitialDelaunay);
   try{
-    tetrahedralize(opts, &in, &out);
+    tetgenbehavior behaviour;
+    behaviour.parse_commandline(opts);
+    tetrahedralize(&behaviour, &in, &out);
   }
   catch (int error){
     Msg::Error("Self intersecting surface mesh");
@@ -521,14 +523,18 @@ void MeshDelaunayVolumeTetgen(std::vecto
             (Msg::GetVerbosity() < 3) ? "Q" : (Msg::GetVerbosity() > 6) ? "V" : "",
             CTX::instance()->mesh.toleranceInitialDelaunay);
     try{
-      tetrahedralize(opts, &in, &out);
+      tetgenbehavior behaviour;
+      behaviour.parse_commandline(opts);
+      tetrahedralize(&behaviour, &in, &out);
     }
     catch (int error){
       Msg::Error("Self intersecting surface mesh, computing intersections "
                  "(this could take a while)");
       sprintf(opts, "dV");
       try{
-        tetrahedralize(opts, &in, &out);
+        tetgenbehavior behaviour;
+        behaviour.parse_commandline(opts);
+        tetrahedralize(&behaviour, &in, &out);
         Msg::Info("%d intersecting faces have been saved into 'intersect.pos'",
                   out.numberoftrifaces);
         FILE *fp = Fopen("intersect.pos", "w");