diff --git a/dune-solvers/iterationsteps/mmgstep.hh b/dune-solvers/iterationsteps/mmgstep.hh
index d4d42cdd45ea036ca1b33900bbcdd597174d223c..9d68cf0e1e5d19ef94b9054b01964e245be25b11 100644
--- a/dune-solvers/iterationsteps/mmgstep.hh
+++ b/dune-solvers/iterationsteps/mmgstep.hh
@@ -52,7 +52,7 @@ public:
                             int numLevels) 
     {
         MultigridStep<OperatorType, DiscFuncType>::setProblem(mat,x,rhs, numLevels);
-        oldCritical.resize(x.size()*dim, false);
+        oldCritical.resize(x.size(), false);
     }
     
     virtual void iterate();