Hmm... if you can edit the php.ini file on your system, then set the SMTP server there. It is under the mail function section. Then use the mail() function to send your e-mail.
Otherwise, perhaps you can initiate a socket conn. to your SMTP (note this is the long way of doing it :-)
$timeout = 60; // in seconds
$fp = fsockopen("smtp.yourisp.com", 25, $errno, $errstr, $timeout);
if(!$fp) {
print "Error $errno: $errstr\n";
}
else {
fwrite($fp, "HELO yourdomain\n");
$response = fread($fp, 512);
fwrite($fp, "MAIL FROM: <email@domain.com>");
....
}
well, you get the idea. Just send in the rest of the SMTP commands to complete your e-mail. If you need help in the SMTP commands, let me know.
-sridhar