Fatal Errors with User Registration and Drupal 6.16!

My site is register-only, but users trying to register would get error, "The argument should be an array in /includes/form.inc on line 1332."

But neither the admin nor user got proper confirmations or emails.

What was worse, a user entry did appear in the db, but trying to access it got this error: "Cannot access empty property in /includes/bootstrap.inc on line 718." Therefore that username and email remained taken.

But when I uninstalled No Case, users could register again, and users were accessible again. I had to use phpMyAdmin to remove the bad user entries from the db. I also had to change my admin passwords back to ones that included caps.

I think that No Case's password-changing thing needs fixed.

So I recommend that no one use No Case on protected sites until this is resolved!