So i'd like to define two groups

One group will all have emails addresses in this format *@xxx.xxx where the x's are known

this group I would like to be able to register by simply sending them an email and not having an admin sign off

for anyone with a different email address I'd like to require an admin to sign off... is there a module or hack to do this?

Seems like it'd be fairly easy to do, i have experience with web programming mainly in asp, if someone could point me to the right places to look to insert some code to do this that would be appreciated as much as an out of the box hack or module.

Thanks,

Bob