Meh. I wish people would just give up on trying to validate email adresses all together (except for maybe basic stuff like checking for an @). They'll almost always forget about some edge case.
I use a pretty ununsual TLD (.su, the old TLD for the Soviet Union, which still remains in the root zone), and from time to time, I come across a site that won't accept my email address because of that. Most of those sites turn out to be generally crappy though, so not much of a loss…
Also, many sites don't accept + in email adresses, which is annoying as hell if you want to use the address extension feature of Postfix et al.
I use a pretty ununsual TLD (.su, the old TLD for the Soviet Union, which still remains in the root zone), and from time to time, I come across a site that won't accept my email address because of that. Most of those sites turn out to be generally crappy though, so not much of a loss…
Also, many sites don't accept + in email adresses, which is annoying as hell if you want to use the address extension feature of Postfix et al.