Craig I think that was true with SQL2000, and the old SQL Mail, but the 2005 and above database mail via msdb.dbo.sp_send_dbmail is already an asynchronous service broker item, so it's safe for use in a trigger, as long as the profile and account have been set up.
I took the OP to mean "mail" or "SMTP Mail" when he said "Outlook", instead of Outlook Profile that was the setup requirement for the old SQL 2000 stuff
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