there is a standard for validating emails. it is described in RFC 3696 - http://tools.ietf.org/html/rfc3696 http://tools.ietf.org/html/rfc3696 one implementat

there is a standard for validating emails. it is described in RFC 3696 - http://tools.ietf.org/html/rfc3696 http://tools.ietf.org/html/rfc3696 one implementation is in lelp - http://www.acooke.org/lepl/rfc3696.html http://www.acooke.org/lepl/rfc3696.html - but that package is no longer maintained (i know, because i wrote it). i don't know of any other implementation. but that's the right way to do it. imho.