Murassmeblade,
Based on your description details above, it's clear that some hostile code is overwriting feilds in your Administrator membership files. To fix this, you'll have to remove that code.
The place to start is locating EVERY write access to the membership files. You can do that fairly easily with a grep at the command line in your Members directory.
If you don't know PERL, I'll be happy to take a look at it for you, or step you through a debuggin procedure. Just let me know.
[email protected]Regards,
Sly