Index: trunk/src/org/openstreetmap/josm/actions/mapmode/DrawAction.java
===================================================================
--- trunk/src/org/openstreetmap/josm/actions/mapmode/DrawAction.java	(revision 393)
+++ trunk/src/org/openstreetmap/josm/actions/mapmode/DrawAction.java	(revision 394)
@@ -140,4 +140,7 @@
 		if (!shift && selection.size() == 1 && selection.iterator().next() instanceof Node) {
 			Node n0 = (Node) selection.iterator().next();
+			if (n0 == n) {
+				return; // Don't create zero length way segments.
+			}
 
 			// alt modifier makes connection to selected node but not existing way