Database mail not sending

I am using the sp_send_dbmail sp and all appears to go well with that. But SS does not seem to be attempting to send the mail.

However when I look at the entries in sysmail_mailitems the sent status is zero. There are no entries in sysmail_log.

I configured Database Mail via the wizard. I am using the Sept CTP.

What could be the problem?I do have the following information in my Sql Alert log:
Unable to start mail session [reason: No Mail Profile defined]

However there are two mail methods defined in 2005, Sql Mail and Database Mail. I have defined a default mail profile in Database Mail. I have define and test one in Sql Mail and it says it works.