diff -r 4d07dd56fa9a -r 4bebc22ab77c src/lemon/dijkstra.h
--- a/src/lemon/dijkstra.h	Fri Mar 04 23:12:10 2005 +0000
+++ b/src/lemon/dijkstra.h	Fri Mar 04 23:14:36 2005 +0000
@@ -451,7 +451,7 @@
     {
       _reached->set(v,true);
       _dist->set(v, dst);
-      _predNode->set(v,G->source((*_pred)[v]));
+      if((*_pred)[v]!=INVALID) _predNode->set(v,G->source((*_pred)[v])); ///\todo What to do?
     }
 
   public:
@@ -751,7 +751,7 @@
     /// This constructor does not require parameters, therefore it initiates
     /// all of the attributes to default values (0, INVALID).
     DijkstraWizardBase() : _g(0), _length(0), _pred(0), _predNode(0),
-		       _dist(0), _source(INVALID) {}
+		       _dist(0), _source(0) {}
 
     /// Constructor.
     
@@ -763,7 +763,7 @@
     /// \param s is the initial value of  \ref _source
     DijkstraWizardBase(const GR &g,const LM &l, Node s=INVALID) :
       _g((void *)&g), _length((void *)&l), _pred(0), _predNode(0),
-		  _dist(0), _source((void *)&s) {}
+		  _dist(0), _source((s==INVALID)?0:(void *)&s) {}
 
   };