mail() failure in PHP 5.2.5 on Windows 2003 w/ Exchange (headers problem)

[rad131304]

I am attempting to get an Echange 2003 server to allow PHP to use it to relay messages.  I know the two are talking to each other because IMF is rejecting the messages - I'm guessing it doesn't like my headers since the rejeciton is by IMF, but I'm not sure what the problem is.

 

$headers = 'From: user@domain.com' . "\r\n" . 'Reply-To: user@domain.com' . "\r\n" . 'X-Mailer: PHP/' . phpversion();
mail("user2@newdomain.com","test subject","test message",$headers,"-r user@domain.com");

 

user@domain.com is a valid exchange email address for this server.

 

Help would be appreciated!