Followup to r1647914 - message text.
I suppose a user will never see this message. The method enumerates a constant list of property names (supported_properties in jk_util.c). All those are known at compilation time. It is a self-check targeted to those who update supported_properties table in the source code.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/jk/trunk@1647980 13f79535-47bb-0310-9956-ffa450edef68