[emodendroket]

I would guess in the many years they've had this they've had to iron out some issues, but allowing you to receive e-mail at all is a denial of service attack vector.

[taeric]

True. But it is only a denial of your email service. Allowing it to leak over to other services is not good.

[emodendroket]

You could think of them as different facets of the same service, like Exchange.