^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$ Description: Email validator that adheres directly to the specification for email address naming. It allows for everything from ipaddress and country-code domains, to very rare characters in the username.
http://www.e137.com/huida/software/emailspider.zip
http://ln-down.skycn.net/down/ssw.zip
我曾使用过一个免费的web service,专门用来验证email,只是不知是否还找得到
http://ws.cdyne.com/emailverify/ev.asmx,你可以用这个webservice来进行验证