Index: /trunk/src/org/openstreetmap/josm/gui/layer/TMSLayer.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/layer/TMSLayer.java	(revision 3920)
+++ /trunk/src/org/openstreetmap/josm/gui/layer/TMSLayer.java	(revision 3921)
@@ -445,5 +445,5 @@
                                 return;
 
-                            if(attrImageBounds.contains(e.getPoint())) {
+                            if(attrImageBounds != null && attrImageBounds.contains(e.getPoint())) {
                                 try {
                                     java.awt.Desktop desktop = java.awt.Desktop.getDesktop();