Index: trunk/src/org/openstreetmap/josm/io/OsmReader.java
===================================================================
--- trunk/src/org/openstreetmap/josm/io/OsmReader.java	(revision 2204)
+++ trunk/src/org/openstreetmap/josm/io/OsmReader.java	(revision 2205)
@@ -488,5 +488,5 @@
                         throw new IllegalDataException(
                                 tr(
-                                        "Relation with external id ''{0}'' refers to missing primitive with external id ''{1}''.",
+                                        "Relation with external id ''{0}'' refers to a missing primitive with external id ''{1}''.",
                                         externalRelationId,
                                         rm.id