[Mediawiki-l] login problems

[Peter Work]

Hi,

A Newbie here. I Just installed mediawiki.1.5.7 on a redhat enterprise 
workstation.

As an anonymous user, I can create new pages, edit & save articles just 
fine. If I log in as a user or even as WikiSysop, I don't seem to be able to 
write back to the database. The SAVE button in the edit window is treated 
like a PREVIEW, I cannot change prefences. As WikiSysop I cannot delete 
pages.

Any suggestions?    Regards, Peter.