Admin;
I understand that we can't use the account registration form right now, but there are still people who want accounts.
Would it be possible to have a stickied topic created for a waiting list, so people can let you know they want an account without gumming up the entire forum with individual "Signup wanted" messages?
That way, you could contact them when registration is enabled again without loads of hassle (like hunting through 100+ forum topics).
One last thought: Account registration in which new users wait until the system upgrade (MYSQL06) is complete before database access is granted.
If you guys lack the time or manpower for that registration page (see above paragraph), I could write it for you and send it in. It'd be a good backup in the event of similar situations cropping up later on.