Index: /trunk/src/org/openstreetmap/josm/data/imagery/ImageryInfo.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/imagery/ImageryInfo.java	(revision 13752)
+++ /trunk/src/org/openstreetmap/josm/data/imagery/ImageryInfo.java	(revision 13753)
@@ -1427,4 +1427,7 @@
      */
     public Map<String, String> getCustomHttpHeaders() {
+        if (customHttpHeaders == null) {
+            return Collections.emptyMap();
+        }
         return customHttpHeaders;
     }