Index: src/org/openstreetmap/josm/data/osm/visitor/MapPaintVisitor.java
===================================================================
--- src/org/openstreetmap/josm/data/osm/visitor/MapPaintVisitor.java	(revision 1490)
+++ src/org/openstreetmap/josm/data/osm/visitor/MapPaintVisitor.java	(working copy)
@@ -256,7 +256,7 @@
 
         if(l != null)
         {
-            color = l.color;
+            if (l.color != null) color = l.color;
             width = l.width;
             realWidth = l.realWidth;
             dashed = l.dashed;