We've had this problem before RC2 and before Joomla. Sometimes, when a user registers, it turns up in the backend as "Pending Approval". CB is set to not require admin approval, but only e-mail confirmation. This issue is resolved by doing a sync between the Joomla users table and the CB users table.
Today it happened again, and I looked at the database.
The ##_users table looks allright, but ##_comprofiler misses the user with the correct id. There's 645 and 647, but no 646. There is, however, a user with id = 0 (as well as user_id) which says approved = 1 and confirmed = 0, just like it should. Will resync now to see what happens with it.
Refreshed.. The 0 userid is still there, but now 646 is present as it should. First, last and middlename is NULL though, the other users got empty fields there. It also says both confirmed and approved. Besides from that, it looks just like 647 does.
Any idea here at all? This is causing us lots of headaches since we need to check the CB users at least once a day.
Happy new year!
Best regards, Oscar