In log4j.xml file, increase logging level to "DEBUG".e.g. in
JBoss\server\all\conf\log4j.xml file,for "DEBUG".e.g.----Once that
is done, server log should provide more details regarding the
authentication failure as specified in the message above. Perhaps it
might contain error code from Active Directory. If the lower level
message contains AD error code, you might be able to look up that error
code on MSDN.