Index: trunk/src/org/openstreetmap/josm/gui/mappaint/MapImage.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/mappaint/MapImage.java	(revision 5254)
+++ trunk/src/org/openstreetmap/josm/gui/mappaint/MapImage.java	(revision 5257)
@@ -65,5 +65,6 @@
                         synchronized (MapImage.this) {
                             if (result == null) {
-                                img = (BufferedImage) MapPaintStyles.getNoIcon_Icon(source).getImage();
+                                ImageIcon noIcon = MapPaintStyles.getNoIcon_Icon(source);
+                                img = noIcon == null ? null : (BufferedImage) noIcon.getImage();
                             } else {
                                 img = (BufferedImage) result.getImage();