--- a/QTfrontend/mapContainer.cpp	Tue Mar 30 20:39:34 2010 +0000
+++ b/QTfrontend/mapContainer.cpp	Tue Mar 30 20:51:25 2010 +0000
@@ -365,7 +365,7 @@
 
     int id = 0;
     for(int i = 0; i < chooseMap->count(); i++)
-        if(chooseMap->itemData(i).toList()[0].toString() == map)
+        if(!chooseMap->itemData(i).isNull() && chooseMap->itemData(i).toList()[0].toString() == map)
         {
             id = i;
             break;