Index: src/org/openstreetmap/josm/data/validation/tests/DuplicateNode.java
===================================================================
--- src/org/openstreetmap/josm/data/validation/tests/DuplicateNode.java	(revision 10916)
+++ src/org/openstreetmap/josm/data/validation/tests/DuplicateNode.java	(working copy)
@@ -419,6 +419,8 @@
         if (!(testError.getTester() instanceof DuplicateNode)) return false;
         // never merge nodes with different tags.
         if (testError.getCode() == DUPLICATE_NODE) return false;
+        // cannot merge nodes outside download area
+        if (testError.getPrimitives().iterator().next().isOutsideDownloadArea()) return false;
         // everything else is ok to merge
         return true;
     }