Anonymous Monk,
As merlyn points out, this is broken - consider: 
.@..ZZZZ

[download]

It is an extremely common mistake to assume what is a valid email SMTP address due to ignorance of the RFC. You should use Email::Valid if your purpose is to determine if a string is a valid formatted SMTP email address (don't know of one that does UUCP or X.400 or CC:Mail email addresses). On the other hand, if your purpose is to specifically look for strings that, while technically valid, are strings you do not want to accept (due to attempting to exploit an open relay for instance), then you need to be very explicit in what your requirements are and we will try to help.

Update: It may be inconceivable to some as to why I would advocate not using Email::Valid in certain circumstances. Here is a short list of nodes that may be worth reading:

Cheers - L~R

In reply to Re: Reg.Exp to validate Email Address by Limbic~Region
in thread Reg.Exp to validate Email Address by Anonymous Monk

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