Index: /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Selector.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Selector.java	(revision 15082)
+++ /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Selector.java	(revision 15083)
@@ -341,5 +341,5 @@
                         addToChildren(e, p);
                     }
-                } else if (e.osm instanceof Relation) {
+                } else if (e.osm instanceof Relation && e.osm.isMultipolygon()) {
                     for (IPrimitive p : Geometry.filterInsideMultipolygon(toCheck, (Relation) e.osm)) {
                         addToChildren(e, p);