Merge r1125646 from trunk:

Some LDAP servers (wrongly) return LDAP_CONSTRAINT_VIOLATION if a user is
locked due to too many password retries. This should not cause an internal
server error but be treated as "auth denied".

Submitted by: sf
Reviewed/backported by: jim



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@1162864 13f79535-47bb-0310-9956-ffa450edef68