log4j documentation patch

Category-documentation.patch

Index: src/main/java/org/apache/log4j/Category.java
===================================================================
--- src/main/java/org/apache/log4j/Category.java	(revision 1363045)
+++ src/main/java/org/apache/log4j/Category.java	(working copy)
@@ -558,6 +558,9 @@
 
   /**
      Returns the assigned {@link Level}, if any, for this Category.
+     The level may be <code>null</code> in which case the <i>effective</i>
+     level is derived from the hierarchy.  You may prefer to
+     {@link #getEffectiveLevel}.
 
      @return Level - the assigned Level, can be <code>null</code>.
   */