I have 5 production installs of WP 2.3.3 on my host, and have installed v2.5.RC1 in my sandbox on the same host. They all share a common user table for the user names and passwords.
I can no longer log into my 2.3.3 blogs using any user that has logged into 2.5.rc1... it gives a password incorrect error. And there has been no changes to the database or usernames or passwords.
I have to physically go into the database and change the md5 password to something else in order to able to log back into the 2.3.3 blogs. It will then work fine again, until I use that username to login to the 2.5.rc1 blog, and then it no longer works again on the 2.3.3 blogs.
Is there a 'bug traker' where I should report this issue, instead of in this forum?