> Do you know that it's going out with valid headers, a "legal" helo
> address,
> and the like? Many mail systems will use these as reasons to reject
> connections when they're wrong. In the case of bad helo values, often it
> won't get as far as the spam filter, since that's sent through before the
> message.
>
> If stuff worked before but now doesn't, another question is whether your
> sending IP is in a range recently blacklisted, if your ISP has been
> hosting spammers.
Yeah, that's another possibility. I *REALLY* DISLIKE this blacklist
attitude of "oh, well, that's out of this DNS host, so we'll block *all*
of their emails, from all the domains they host".
Do try to telnet to port 25 for google mail, and see if it'll talk to you,
or if you can get through at all.
mark