Works fine to my internal mail server. Depends what type of connection you're using, but bear in mind that by attempting to send to those external servers your IP may be getting rejected by various anti-spam techniques (reverse DNS, etc.). For instance, outbound SMTP via my cable connection doesn't work, period, as my ISP has their IP blocks registered with most major RBLs as ones that should never send SMTP mail. Your best bet would be a server that
requires authenticated SMTP (the "account" setting in the DNS-343), but there aren't many of those.
That said, it'd be reeeeally nice to have a syslog to troubleshoot things like this...
