md5/password/lala

I use my forum user database for other applications I wrote with php.
I took the "md5" encryption out of the VB code, so new users' passwords are added in normal text, and changed the existing users' passwords (all close friends, I know their passwords by heart) to what they wanted...

Now, I upgraded the forums, edited some files (member.php) and now users can login into the forum again. But I can't access the admin control panel.

Any ideas?

[Admin]

Have you edited sessions.php as well?
More to the point, this line:

    if (md5($loginpassword)!=$bbuserinfo[password]) {