diff --git a/src/core/mpi/MPIWrapper.h b/src/core/mpi/MPIWrapper.h
index 9caab0b13cf546a723471386149777469d8018af..89112fd6f2150a308f6e7bdeb8542ce36ff97174 100755
--- a/src/core/mpi/MPIWrapper.h
+++ b/src/core/mpi/MPIWrapper.h
@@ -45,7 +45,11 @@
 
 #endif
 
-
+namespace walberla {
+namespace mpistubs {
+    //empty namespace which can be used
+} // namespace mpistubs
+} // namespace walberla
 
 #ifdef WALBERLA_BUILD_WITH_MPI