Index: src/org/openstreetmap/josm/actions/mapmode/ExtrudeAction.java
===================================================================
--- src/org/openstreetmap/josm/actions/mapmode/ExtrudeAction.java	(revision 3631)
+++ src/org/openstreetmap/josm/actions/mapmode/ExtrudeAction.java	(working copy)
@@ -323,7 +323,7 @@
                     //find if the new points overlap existing segments (in case of 90 degree angles)
                     Node nextNode = getNextNode(selectedSegment.lowerIndex + 1);
                     nodeOverlapsSegment = nextNode != null && segmentsParralel(initialN2en, nextNode.getEastNorth(), initialN2en, newN2en);
-                    hasOtherWays = hasNodeOtherWays(selectedSegment.getFirstNode(), selectedSegment.way);
+                    hasOtherWays = hasNodeOtherWays(selectedSegment.getSecondNode(), selectedSegment.way);
 
                     if (nodeOverlapsSegment && !alwaysCreateNodes && !hasOtherWays) {
                         //move existing node