#014451: $workflow->nodes does not return all nodes

after modifying a workflow $workflow->nodes sometimes fails to return all nodes. in such a case
the number should be the same.

see code fragment

when you comment out the first two echo's then the code returns the correct result.
the call to $workflow->nodes makes it fail.

No resolution found

Operating System:
PHP Version: (please be specific, like '4.4.3' or '5.1.5')
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Browser (and version):

  $w = new ezcWorkflow('test');
  
  $w->startNode->addOutNode($w->endNode);
  
  // If you remove this statement then the workflow counting works 
  echo "1count workflow:".count($w)."<br/>";
  echo "1count nodes:".count($w->nodes)."<br/>";
  
  $w->startNode->removeOutNode($w->endNode);
  
  // wait for input into the workflow variable value.
  $input = new ezcWorkflowNodeInput( array( 'value' => new ezcWorkflowConditionIsInteger() ) );
  $w->startNode->addOutNode( $input );
  
  // create the exclusive choice branching node
  $choice = new ezcWorkflowNodeExclusiveChoice;
  $input->addOutNode( $choice );
  
  $branch1 = new ezcWorkflowNodeInput( array( 'value' => new ezcWorkflowConditionIsAnything() ) ); // create nodes for the first branch of execution here..
  $branch2 = new ezcWorkflowNodeInput( array( 'value' => new ezcWorkflowConditionIsAnything() ) ); // create nodes for the second branch of execution here..
  
  // add the outnodes and set the conditions on the exclusive choice
  $choice->addConditionalOutNode( new ezcWorkflowConditionIsAnything() , $branch1 );
  $choice->addConditionalOutNode( new ezcWorkflowConditionIsAnything() , $branch2 );
  
  // Merge the two branches together and continue execution.
  $merge = new ezcWorkflowNodeSimpleMerge();
  $merge->addInNode( $branch1 );
  $merge->addInNode( $branch2 );
  $merge->addOutNode( $w->endNode );
  echo "2count workflow:".count($w)."<br/>";
  echo "2count nodes:".count($w->nodes)."<br/>";

OUTPUT:
1count workflow:2
1count nodes:2
2count workflow:7
2count nodes:6