req: help with mail on IIS 6

Hi All: Just joined the list. I'm having problems configuring mail in PHP. I have PHP 5.2.9 installed on server 2003 std with sp2 installed. The default SMTP service is running. I'm running Wordpress without any problems, except for configuring mail. My php.ini file looks like: [mail function] ; For Win32 only. ;smtp = localhost ;smtp = 127.0.0.1 smtp = 192.168.1.6 smtp_port = 25 ; For Win32 only. sendmail_from = me@mydomain.com I've tried each of the three server addresses above, and none of them work. If I try to run a simple test like: <?php $to = "me@mydomain.com"; $subject = "Test mail"; $message = "Hello! This is a simple email message."; $from = "me@mydomain.com"; $headers = "From: $from"; mail($to,$subject,$message,$headers); echo "Mail Sent."; ?> I don't receive an error, but the mail does not get sent. There's no entry in the SMTP log, and nothing gets dropped in the "pickup" or "queue" folders for the SMTP service. I tried explicitly adding "allow" entries in the SMTP configuration for the above names/IPs, and also in the "relaying" section, but still nothing. What can I do to debug? TIA- da' noob