https://bugzilla.wikimedia.org/show_bug.cgi?id=55190
--- Comment #3 from Kunal Mehta (Legoktm) legoktm.wikipedia@gmail.com --- It has very much to do with LDAP: http://www.mediawiki.org/wiki/Extension:LDAP%5C_Authentication/User%5C_Provi...
And it has very much to do with Linux: Linux path names are case sensitive.
I reported the bug as it took me time to track down and perhaps someone else who has the misfortune of dealing with it will find this helpful.
The fact is that if I can login with a lower case name, and I can, then whatever pywiki stores should be in the same case, NOT what may be returned when the wiki user name is returned. The file name for *-login.data should be the same case as what is stored in user-config.py
This is just good practice, especially on a case sensitive host like Linux.
Also, as mediawiki is authenticating against LDAP, whatever it stores as the username is irrelevant if it correctly authenticates. A further reason to enforce correct casing based on the user-config.py file.