diff -r fd82adfbe905 -r 22099ef840d7 lemon/bits/alteration_notifier.h
--- a/lemon/bits/alteration_notifier.h	Mon Nov 21 12:07:05 2005 +0000
+++ b/lemon/bits/alteration_notifier.h	Mon Nov 21 17:48:00 2005 +0000
@@ -439,6 +439,67 @@
       undir_edge_notifier.clear();
     }
   };
+
+
+  template <typename _Base>
+  class AlterableUndirBipartiteGraphExtender : public _Base {
+  public:
+
+    typedef _Base Parent;
+    typedef AlterableUndirBipartiteGraphExtender Graph;
+  
+    typedef typename Parent::Node Node;
+    typedef typename Parent::LowerNode LowerNode;
+    typedef typename Parent::UpperNode UpperNode;
+    typedef typename Parent::Edge Edge;
+    typedef typename Parent::UndirEdge UndirEdge;
+  
+  
+    typedef AlterationNotifier<Node> NodeNotifier;
+    typedef AlterationNotifier<LowerNode> LowerNodeNotifier;
+    typedef AlterationNotifier<UpperNode> UpperNodeNotifier;
+    typedef AlterationNotifier<Edge> EdgeNotifier;
+    typedef AlterationNotifier<UndirEdge> UndirEdgeNotifier;
+
+  protected:
+
+    mutable NodeNotifier nodeNotifier;
+    mutable LowerNodeNotifier lowerNodeNotifier;
+    mutable UpperNodeNotifier upperNodeNotifier;
+    mutable EdgeNotifier edgeNotifier;
+    mutable UndirEdgeNotifier undirEdgeNotifier;
+
+  public:
+
+    NodeNotifier& getNotifier(Node) const {
+      return nodeNotifier;
+    }
+
+    LowerNodeNotifier& getNotifier(LowerNode) const {
+      return lowerNodeNotifier;
+    }
+
+    UpperNodeNotifier& getNotifier(UpperNode) const {
+      return upperNodeNotifier;
+    }
+
+    EdgeNotifier& getNotifier(Edge) const {
+      return edgeNotifier;
+    }
+
+    UndirEdgeNotifier& getNotifier(UndirEdge) const {
+      return undirEdgeNotifier;
+    }
+
+    ~AlterableUndirBipartiteGraphExtender() {
+      nodeNotifier.clear();
+      lowerNodeNotifier.clear();
+      upperNodeNotifier.clear();
+      edgeNotifier.clear();
+      undirEdgeNotifier.clear();
+    }
+
+  };
   
 /// @}