Index: /trunk/src/org/openstreetmap/josm/data/validation/tests/TagChecker.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/validation/tests/TagChecker.java	(revision 10223)
+++ /trunk/src/org/openstreetmap/josm/data/validation/tests/TagChecker.java	(revision 10224)
@@ -213,5 +213,7 @@
                             break;
                         default:
-                            Main.warn("Unsupported TagChecker key: " + key);
+                            if (!key.startsWith(";")) {
+                                Main.warn("Unsupported TagChecker key: " + key);
+                            }
                         }
                     } else if (tagcheckerfile) {