Index: /trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMSLayerPanel.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMSLayerPanel.java	(revision 14174)
+++ /trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMSLayerPanel.java	(revision 14175)
@@ -182,6 +182,9 @@
             }
         } else {
-            info = wms.toImageryInfo(getImageryName(), tree.getSelectedLayers(), (List<String>) null, true); // TODO: ask user about transparency
-            info.setUrl(getWmsUrl());
+            if (wms != null && wms.buildRootUrl() != null) {
+                info = wms.toImageryInfo(getImageryName(), tree.getSelectedLayers(), (List<String>) null, true); // TODO: ask user about transparency
+            } else {
+                info = new ImageryInfo(getImageryName(), getWmsUrl());
+            }
             info.setImageryType(ImageryType.WMS);
         }