Problem with Moderator Profile

One of my users can't edit her own profile anymore since I made her a moderator. She gets this message:

Bad HTTP_REFERER. You were referred to this page from an unauthorized source. Please go back and try again. If the problem persists please make sure that 'Base URL' is correctly set in Admin/Options and that you are visiting the forum by navigating to that URL.

She didn't have any problems before she became a moderator, and everything else works just fine.

I've logged in with her username, and I didn't have any problems with editing her profile, but she still has the same problem...

I've also tried making her a normal user again. When I did, she could edit her profile again. But when I made her a moderator again, the problem returned.

any ideas ?

Olorin