problem sending emamil across one postfix server

Hello i want from one php page to send emails but i have one great problem. The server is one postfix into one suse and the php pages are into the same server with apache 2 and php 5. it doesn't sent the messages and into the email server logs appears this: Jan 3 16:28:55 server postfix/pickup[18946]: 7F6C978557: uid=30 from=<wwwrun> Jan 3 16:28:55 server postfix/cleanup[18976]: 7F6C978557: message-id=<20080103152855.7F6C978557@server.MI_DOMINIO.org> Jan 3 16:28:55 server postfix/qmgr[18947]: 7F6C978557: from=<wwwrun@server.MI_DOMINIO.org>, size=722, nrcpt=1 (queue active) Jan 3 16:28:55 server postfix/qmgr[18947]: 7F6C978557: to=<infocuenta@server.MI_DOMINIO.org>, orig_to=<info@cuenta.com>, relay=none, delay=0, status=deferred (delivery temporarily suspended: transport is unavailable) My emamils from the php page i send using this: /* recipients */ $to = "info@MI_DOMINIO.com"; //$nombre . " <" . $email. ">"; /* subject */ $subject = "Email desde la pagina web"; /* message */ $message = " <html> <head> </head> <body> <p>Has recibido este correo desde el formulario de la pagina web.</p> <p> Nombre: $nombre <br> Email: $email <br> Asunto del mensaje: $asunto </p> </body> </html> "; /* To send HTML mail, you can set the Content-type header. */ $headers = "MIME-Version: 1.0\r\n"; $headers .= "Content-type: text/html; charset=iso-8859-1\r\n"; /* additional headers */ $headers .= "From: " . $nombre . " <" . $email. ">"; /* and now mail it */ mail($to, $subject, $message, $headers); ?> but it doesn't send Can you help me? thanks