I have a wordpress 3.2.1 installation for an intranet blog, protected by the members-only-Plugin and interfaced with the LDAP Authenticator-Plugin to my OpenLDAP-Server. Before those, I ran through a bunch of other plugins, which all have been uninstalled. The LDAP Authenticator basically authenticates the user against the LDAP and - if no user data exists in wordpress - adds the user with the role "author".
During this test phase, I had two users to test the plugins. Now, in production, those two users may login, but will always lose their role information, so that their role is reset to "none". It does not matter, if they did have a role before or if I delete the users completely first and change their role to something else - as soon as they login, their role is deleted.
Please note, that I do not use automatic role change via an LDAP-Group or a similar method, but only manual setting of the role. This only is true for two out of a hundred users. Beside deleting and recreating them, I checked the wp_users and wp_usermeta for any differences of their profile to other users (none found) and I also diffed the codebase to a fresh installation I have to find any stuff left from some of the old plugins (also none found).
Beside the reinstallation of the whole blog - did anyone have this problem in the past? Any more hints on where I could look? I already asked at the wordpress.org-forums, but the chance of an answer is very slim there.