Index: /trunk/src/org/openstreetmap/josm/gui/MainApplication.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 11102)
+++ /trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 11103)
@@ -113,5 +113,7 @@
     @Override
     protected void shutdown() {
-        mainFrame.storeState();
+        if (mainFrame != null) {
+            mainFrame.storeState();
+        }
         super.shutdown();
     }