But really, you're now being too generous. The real solution is to use Email::Valid, which contains a very large and complex regex, plus a few other validation routines.
Well, my point was that you cannot validate the email with a regular expression anyway. You are very unlikely to even catch typos. If my email is bill@microsoft.com and I mistype it as bikk@microsoft.com how is Email::Valid going to help you? So why bother at all?
Concession: Email::Valid can also check if an MX entry exists for the domain. That might make sense in some situations (but it still does not check the user name -- is there a way to do this, too?)
