Okay, god damn it.
Apparently, sbcglobal has some antispam crap in place so that you can only send out so many emails per …day? Hour? I have no idea.
After you exceed whatever random threshold they’ve set, you get a cute little message like this:
Oct 17 18:20:03 crossbone postfix/smtp[25848]: 3143F43F73: to=<email address goes here>, relay=smtp.sbcglobal.net[207.115.20.26]:25, delay=0.73, delays=0.27/0.03/0.4/0.03, dsn=4.7.7, status=deferred (host smtp.sbcglobal.net[207.115.20.26] said: 451 4.7.7 Mail access temporarily suspended for 76.243.28.8**BCMI**flpi102 (in reply to MAIL FROM command))
SBC: While I commend your efforts to kill spam, I think you might have set the threshold a little low.
