I tried this on my SME 6.5 and it rejected due to the @ in the email address
"The pseudonym should contain only lower-case letters, numbers, period, hyphen and underscore and should start with a lower-case letter or number. For example "sales", "john.holland", "123" and "email-administrator" are all valid pseudonyms, but "John Smith" and "Henry Miller" are not."
Is this only available in v7 onwards?
Steve B