drupal_mail_send sendmail may sometimes need -f envelope sender address

Looks like something similar has already been added to 7.x. (modules/system/system.mail.inc:43)

This fixes mail on my system.

--- includes/mail.inc.orig 2010-09-18 09:21:59.000000000 -0700
+++ includes/mail.inc 2010-09-18 09:22:08.000000000 -0700
@@ -189,7 +189,8 @@
str_replace("\r", '', $message['body']),
// For headers, PHP's API suggests that we use CRLF normally,
// but some MTAs incorrecly replace LF with CRLF. See #234403.
- join("\n", $mimeheaders)
+ join("\n", $mimeheaders),
+ '-f'.$message['headers']['From']
);
}
}