diff --git a/include/hpp/manipulation/problem-solver.hh b/include/hpp/manipulation/problem-solver.hh
index 75a86dc76e5adf9df2cbc13cf757e4c0f6f998fb..d37ee93306c3ecf4eb03d2b8e477f8aae945513d 100644
--- a/include/hpp/manipulation/problem-solver.hh
+++ b/include/hpp/manipulation/problem-solver.hh
@@ -41,7 +41,7 @@ namespace hpp {
         {}
 
         ProblemSolver () :
-          core::ProblemSolver (), robot_ (), graspsMap_()
+          core::ProblemSolver (), robot_ (), problem_ (0x0), graspsMap_()
         {
         }