ok thanks. I thought that

benf — Tue, 22 Mar 2011 12:58:32 +0000

ok thanks. I thought that might be the case.

It looks like PHP's mail

pr0gr4mm3r — Tue, 22 Mar 2011 12:08:43 +0000

It looks like PHP's mail function in Linux relies on sendmail which does not easily support external SMTP servers.

I usually just let it send mail from the same server. The negative to that is that if you are on a dynamic IP, they are frequently blacklisted for spam.

For past projects, I used a class called HTMLMimeMail5 (seems to be renamed to RMail). This allows the remote SMTP server to be specified as well as several other options.