When were custom sounds for e-mail notification alerts introduced in iOS? When were custom sounds for e-mail notification alerts introduced in iOS?

I know that for SMS/MMS/messages they were introduced with iOS 5.0. Now I always thought e-mail sounds could be changed since 4.x..?

(custom sounds = the ones you create yourself and import by using iTunes on a computer)
Nope, this is all new. Before iOS 5 you could only set the ringer's sound to a custom one. If you ask me, it's about time!