Hey Mark,
                I've got the same problem as yours and i've been restlessly trying to fix it.
                Its been 2 days now and i still cant figure what to do.It seems that rlm_ldap
                is not able to authenticate to the user credentials that you've specified, is that
                right? Even I get the successful bind but not authentication.
                If ya come across a solution, please lemme know... thanks in advance :)