Stop registration for users with a certain email domain?

[dontpanic]

How can I stop users from registering if they're using a certain email domain? I don't want them to be able to register at all using that email domain? For example, just say @gmail.com.

This is for vB 3.0.

Thanks!!

[zappsan]

vBulletin Options > User Banning Options > Banned Email Addresses

[dontpanic]

Great, thanks!! I had obviously missed that option earlier.