/Edit: Sorry for beating a dead horse. I know TLDs are not used the way I think they should be used. But I think it was important to point out once again that this is a dirty hack. It works, but when working outside of the spec you should be aware of it a accept shortcomings. Not saying you should not ask google to route around it. But it has it limits. ".at" are meant for Austria and not for email providers, that's something they just should deal with.