I voted down, but the code looks good, it should be a plus 1 from me.

Check your containers for your TLD parsing... ([a-zA-Z0-9]{2,4})+ would match [a-zA-Z0-9] one to inf times. It shouldn't be encapsulated at all.

Also, you have the host and sub host separation parsing good, but the local name parsing allows an infinite number of periods in a row.

-CB

Email::Valid on CPAN has much better capabilities, and won't fail on .museum.

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Sasha Chorny, http://chorny.net