diff --git a/lemon/smart_graph.h b/lemon/smart_graph.h
--- a/lemon/smart_graph.h
+++ b/lemon/smart_graph.h
@@ -2,7 +2,7 @@
  *
  * This file is a part of LEMON, a generic C++ optimization library.
  *
- * Copyright (C) 2003-2008
+ * Copyright (C) 2003-2009
  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
  * (Egervary Research Group on Combinatorial Optimization, EGRES).
  *
@@ -55,7 +55,7 @@
 
   public:
 
-    typedef SmartDigraphBase Graph;
+    typedef SmartDigraphBase Digraph;
 
     class Node;
     class Arc;
@@ -67,7 +67,7 @@
       : nodes(_g.nodes), arcs(_g.arcs) { }
 
     typedef True NodeNumTag;
-    typedef True EdgeNumTag;
+    typedef True ArcNumTag;
 
     int nodeNum() const { return nodes.size(); }
     int arcNum() const { return arcs.size(); }
@@ -191,14 +191,10 @@
   ///It is also quite memory efficient, but at the price
   ///that <b> it does support only limited (only stack-like)
   ///node and arc deletions</b>.
-  ///It conforms to the \ref concepts::Digraph "Digraph concept" with
-  ///an important extra feature that its maps are real \ref
-  ///concepts::ReferenceMap "reference map"s.
+  ///It fully conforms to the \ref concepts::Digraph "Digraph concept".
   ///
   ///\sa concepts::Digraph.
   class SmartDigraph : public ExtendedSmartDigraphBase {
-  public:
-
     typedef ExtendedSmartDigraphBase Parent;
 
   private:
@@ -225,15 +221,15 @@
 
     ///Add a new node to the digraph.
 
-    /// \return the new node.
-    ///
+    /// Add a new node to the digraph.
+    /// \return The new node.
     Node addNode() { return Parent::addNode(); }
 
     ///Add a new arc to the digraph.
 
     ///Add a new arc to the digraph with source node \c s
     ///and target node \c t.
-    ///\return the new arc.
+    ///\return The new arc.
     Arc addArc(const Node& s, const Node& t) {
       return Parent::addArc(s, t);
     }
@@ -305,7 +301,9 @@
       Node b = addNode();
       nodes[b._id].first_out=nodes[n._id].first_out;
       nodes[n._id].first_out=-1;
-      for(int i=nodes[b._id].first_out;i!=-1;i++) arcs[i].source=b._id;
+      for(int i=nodes[b._id].first_out; i!=-1; i=arcs[i].next_out) {
+        arcs[i].source=b._id;
+      }
       if(connect) addArc(n,b);
       return b;
     }
@@ -420,7 +418,7 @@
 
   public:
 
-    typedef SmartGraphBase Digraph;
+    typedef SmartGraphBase Graph;
 
     class Node;
     class Arc;
@@ -464,8 +462,8 @@
       explicit Arc(int id) { _id = id;}
 
     public:
-      operator Edge() const { 
-        return _id != -1 ? edgeFromId(_id / 2) : INVALID; 
+      operator Edge() const {
+        return _id != -1 ? edgeFromId(_id / 2) : INVALID;
       }
 
       Arc() {}
@@ -480,6 +478,13 @@
     SmartGraphBase()
       : nodes(), arcs() {}
 
+    typedef True NodeNumTag;
+    typedef True EdgeNumTag;
+    typedef True ArcNumTag;
+
+    int nodeNum() const { return nodes.size(); }
+    int edgeNum() const { return arcs.size() / 2; }
+    int arcNum() const { return arcs.size(); }
 
     int maxNodeId() const { return nodes.size()-1; }
     int maxEdgeId() const { return arcs.size() / 2 - 1; }
@@ -620,16 +625,12 @@
   /// It is also quite memory efficient, but at the price
   /// that <b> it does support only limited (only stack-like)
   /// node and arc deletions</b>.
-  /// Except from this it conforms to
-  /// the \ref concepts::Graph "Graph concept".
-  ///
-  /// It also has an
-  /// important extra feature that
-  /// its maps are real \ref concepts::ReferenceMap "reference map"s.
+  /// It fully conforms to the \ref concepts::Graph "Graph concept".
   ///
   /// \sa concepts::Graph.
-  ///
   class SmartGraph : public ExtendedSmartGraphBase {
+    typedef ExtendedSmartGraphBase Parent;
+
   private:
 
     ///SmartGraph is \e not copy constructible. Use GraphCopy() instead.
@@ -647,8 +648,6 @@
 
   public:
 
-    typedef ExtendedSmartGraphBase Parent;
-
     /// Constructor
 
     /// Constructor.
@@ -657,15 +656,15 @@
 
     ///Add a new node to the graph.
 
-    /// \return the new node.
-    ///
+    /// Add a new node to the graph.
+    /// \return The new node.
     Node addNode() { return Parent::addNode(); }
 
     ///Add a new edge to the graph.
 
     ///Add a new edge to the graph with node \c s
     ///and \c t.
-    ///\return the new edge.
+    ///\return The new edge.
     Edge addEdge(const Node& s, const Node& t) {
       return Parent::addEdge(s, t);
     }
@@ -728,8 +727,8 @@
         dir.push_back(arcFromId(n));
         dir.push_back(arcFromId(n-1));
         Parent::notifier(Arc()).erase(dir);
-        nodes[arcs[n].target].first_out=arcs[n].next_out;
-        nodes[arcs[n-1].target].first_out=arcs[n-1].next_out;
+        nodes[arcs[n-1].target].first_out=arcs[n].next_out;
+        nodes[arcs[n].target].first_out=arcs[n-1].next_out;
         arcs.pop_back();
         arcs.pop_back();
       }