diff --git a/include/hpp/manipulation/graph/graph-component.hh b/include/hpp/manipulation/graph/graph-component.hh
index 0c4e769686cb3b3a941e5a1ec3037897689656e5..9007b9e4ae53800fc28564411a6a8e1c52722d78 100644
--- a/include/hpp/manipulation/graph/graph-component.hh
+++ b/include/hpp/manipulation/graph/graph-component.hh
@@ -100,6 +100,9 @@ namespace hpp {
           /// Print the component in DOT language.
           virtual std::ostream& dotPrint (std::ostream& os, dot::DrawingAttributes da = dot::DrawingAttributes ()) const;
 
+          /// Declare a component as dirty
+          void setDirty();
+
         protected:
           /// Initialize the component
           void init (const GraphComponentWkPtr_t& weak);
@@ -120,10 +123,7 @@ namespace hpp {
 
           bool isInit_;
 
-          void throwIfNotInitialized () const
-          {
-            if (!isInit_) throw std::logic_error ("The graph should have been initialized first.");
-          }
+          void throwIfNotInitialized () const;
 
           /// Print the object in a stream.
           virtual std::ostream& print (std::ostream& os) const;
diff --git a/include/hpp/manipulation/problem.hh b/include/hpp/manipulation/problem.hh
index c7c318b5db32f81ed8300fe833845b1ad5cda92a..34bc9e48476fa46b12655512255de19d889ad403 100644
--- a/include/hpp/manipulation/problem.hh
+++ b/include/hpp/manipulation/problem.hh
@@ -74,11 +74,7 @@ namespace hpp {
 
         void setPathValidationFactory (
             const core::PathValidationBuilder_t& factory,
-            const value_type& tol)
-        {
-          pvFactory_ = factory;
-          pvTol_ = tol;
-        }
+            const value_type& tol);
 
       private:
         /// The graph of constraints
diff --git a/src/graph/graph-component.cc b/src/graph/graph-component.cc
index b53bfd0a08b04fac7e4c91f5ff75c3c31526f139..b609ea8eb1383f220a87be13f11413f555356518 100644
--- a/src/graph/graph-component.cc
+++ b/src/graph/graph-component.cc
@@ -45,6 +45,11 @@ namespace hpp {
         return os;
       }
 
+      void GraphComponent::setDirty()
+      {
+        isInit_ = false;
+      }
+
       void GraphComponent::addNumericalConstraint (const NumericalConstraintPtr_t& nm,
           const segments_t& passiveDofs)
       {
@@ -132,6 +137,11 @@ namespace hpp {
         wkPtr_ = weak;
       }
 
+      void GraphComponent::throwIfNotInitialized () const
+      {
+        if (!isInit_ || (graph_.lock() && !graph_.lock()->isInit_)) throw std::logic_error ("The graph should have been initialized first.");
+      }
+
       std::ostream& operator<< (std::ostream& os,
           const hpp::manipulation::graph::GraphComponent& graphComp)
       {
diff --git a/src/problem.cc b/src/problem.cc
index 78a1b72cad15825c164815fb4ee90e9a14811d27..69a00b26049d662dddde3edd8560482f5503a589 100644
--- a/src/problem.cc
+++ b/src/problem.cc
@@ -21,6 +21,7 @@
 #include <hpp/manipulation/weighed-distance.hh>
 #include <hpp/manipulation/graph-steering-method.hh>
 #include <hpp/manipulation/graph-path-validation.hh>
+#include <hpp/manipulation/graph/graph.hh>
 
 namespace hpp {
   namespace manipulation {
@@ -73,5 +74,14 @@ namespace hpp {
       return HPP_DYNAMIC_PTR_CAST (SteeringMethod,
           Parent::steeringMethod());
     }
+
+    void Problem::setPathValidationFactory (
+        const core::PathValidationBuilder_t& factory,
+        const value_type& tol)
+    {
+      pvFactory_ = factory;
+      pvTol_ = tol;
+      if (graph_) graph_->setDirty();
+    }
   } // namespace manipulation
 } // namespace hpp