Just installed a clean WP 1.5.2. A complete newbie registered with username:
When John tried to login, the system claimed that his username did not exist. I looked in the database, and his username was stored as:
So either two things need to be done: (1) Do not allow users to register usernames containing any non-alphanumeric characters, or (2) don't escape single quotes when a user registers.
Is there a plug-in that can perform either function, or is this a bug?