Same Problem for me. Although I know: It’s a problem with the mail attribute.
My Server issues the name “mail” for the attribute. When loging in a new user I get the same error “Maybe a realm violation”. When I subistute the attribute on the Admin Site with a wrong name (i.e. “email”) and login the new user it works fine, without syncing the e-mail-address from the LDAP server. Then changing the attribute back to “mail”, and login the before mentioned user in again syncronizes the e-mail-address from the LDAP server.
What to do?
