diff -Naur orig-org/apache/log4j/Category.java org/apache/log4j/Category.java
--- orig-org/apache/log4j/Category.java	2010-04-08 23:59:20.000000000 +1200
+++ org/apache/log4j/Category.java	2010-11-05 15:56:06.000000000 +1300
@@ -311,7 +311,8 @@
     case Priority.FATAL_INT:
       return LocationAwareLogger.ERROR_INT;
     default:
-      throw new IllegalStateException("Unknown Priority " + p);
+      //throw new IllegalStateException("Unknown Priority " + p);
+      return LocationAwareLogger.DEBUG_INT;
     }
   }