Oh, I don't know. I don't use SQL Server to send emails except for alerts. If I had to do that, I'd probably go to Powershell for it anyway. There's no reason why you couldn't include a backup in an email from there, although that's potentially a big file to be emailing around.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning