Never got an answer but for my purpose I just wrote the following code. Thanks.
update email_table
set good_email = 'Y'
where
(CHARINDEX(' ', LTRIM(RTRIM(email_address))) = 0) AND
(LEFT(LTRIM(email_address), 1) <> '@') AND
(RIGHT(RTRIM(email_address), 1) <> '.') AND
(CHARINDEX('.', email_address, CHARINDEX('@', email_address)) - CHARINDEX('@', email_address) > 1) AND
(LEN(LTRIM(RTRIM(email_address))) - LEN(REPLACE(LTRIM(RTRIM(email_address)), '@', '')) = 1) AND
(CHARINDEX('.', REVERSE(LTRIM(RTRIM(email_address)))) in (3,4)) AND
(CHARINDEX('.@', email_address) = 0 AND CHARINDEX('..', email_address) = 0 )