Index: /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Condition.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Condition.java	(revision 10588)
+++ /trunk/src/org/openstreetmap/josm/gui/mappaint/mapcss/Condition.java	(revision 10589)
@@ -147,4 +147,12 @@
             case CONTAINS:
                 return testString != null && testString.contains(prototypeString);
+            case GREATER_OR_EQUAL:
+            case GREATER:
+            case LESS_OR_EQUAL:
+            case LESS:
+                // See below
+                break;
+            default:
+                throw new AssertionError();
             }