Stopped sending mail

[seattlelion]

I just upgraded from freeBSD 9.0 to 9.1 (nothing else). Roundcube works for receiving mail but won't send it. (It looks like it is sending in the UI, but no delivery, no maillog activity, and nothing in the "sent" mailbox). The error log has no entries either. Any idea what I can do to hunt down this problem?

[SKaero]

If your using smtp try enabling smtp_debug as see if that gets you any information.

[seattlelion]

Where would I specify smtp_debug? I am using imap via dovecot/postfix. I tail'd maillog and nothing is getting in to it when I send from roundcube..no roundcube errors and the message disappears as though sent. I reran roundcube setup and the testmail worked fine from the same accounts that I am accessing via roundcube. No messages in the roundcube log either.

What can this be?

[SKaero]

The option is in <RC root>/config/main.inc.php