[Postfix-es] Problema con mi postfix enviando correo usando php

[Miren Urkixo]

hola a ver si me podeis ayudar por favor.
Estoy desesperada, llevo ya dos semanas intentando arreglar este problema 
pero no doy con ello.
Tengomi postfix en una linux suse 10 y en este mismo servidor hay un apache 
con php
nunca me deja enviar correos desde la propia maquina con php, en el log del 
postfix me aparece simpre cosas de este pelo:
Jan  5 13:52:02 server postfix/pickup[16768]: 20EB589B68: uid=30 
from=<miname en midomain.com>
Jan  5 13:52:02 server postfix/cleanup[17322]: 20EB589B68: 
message-id=<20080105125202.20EB589B68 en server.midomain.com>
Jan  5 13:52:02 server postfix/qmgr[7450]: 20EB589B68: 
from=<miname en midomain.com>, size=394, nrcpt=1 (queue active)
Jan  5 13:52:02 server postfix/qmgr[7450]: 20EB589B68: 
to=<miname en server.midomain.com>, orig_to=<miname en midomain.com>, 
relay=none,delay=0, status=deferred (delivery temporarily suspended: 
transport is unavailable)



Para enviar correo sigo el manual del php al pie de la letra pero me da que 
esto es de postfix (os pongo la forma que tengo de manar emails aqui abajo y 
os añado ahora la salida postconf -n del postfix a ver si me podeis ayudar.
Muchisimas gracias por adelantado y un saludo.

server:~ # postconf -n
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
body_checks = regexp:/etc/postfix/body_checks
broken_sasl_auth_clients = yes
canonical_maps = hash:/etc/postfix/canonical
command_directory = /usr/sbin
config_directory = /etc/postfix
content_filter = smtp-amavis:[127.0.0.1]:10024
daemon_directory = /usr/lib/postfix
debug_peer_level = 15
defer_transports =
header_checks = regexp:/etc/postfix/header_checks
html_directory = /usr/share/doc/packages/postfix/html
inet_interfaces = all
local_recipient_maps = unix:passwd.byname $alias_maps
mail_name = ESMTP
mail_owner = postfix
mail_spool_directory = /var/mail
mailbox_command =
mailbox_size_limit = 51200000
mailbox_transport =
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man
masquerade_classes = envelope_sender, header_sender, header_recipient
masquerade_domains =
masquerade_exceptions = root
message_size_limit = 10240000
mydestination = 
localhost.$mydomain,$myhostname,dominio1.com,dominio2.com,dominion.info
mydomain = midominio.org
myhostname = server.midominio.org
newaliases_path = /usr/bin/newaliases
queue_directory = /var/spool/postfix
readme_directory = /usr/share/doc/packages/postfix/README_FILES
relay_domains = $mydestination
relayhost =
relocated_maps = hash:/etc/postfix/relocated
sample_directory = /usr/share/doc/packages/postfix/samples
sender_canonical_maps = hash:/etc/postfix/sender_canonical
sendmail_path = /usr/sbin/sendmail
setgid_group = maildrop
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtpd_banner = ESMTP
smtpd_client_restrictions = permit_mynetworks,permit_sasl_authenticated
smtpd_error_sleep_time = 0
smtpd_helo_required = yes
smtpd_helo_restrictions =
smtpd_recipient_restrictions = reject_non_fqdn_sender, 
reject_non_fqdn_recipient,                      permit_mynetworks, 
permit_sasl_authenticated, 
reject_unauth_destination,                      reject_unauth_pipelining, 
warn_if_reject,                          permit
smtpd_sasl_auth_enable = yes
smtpd_sasl_local_domain = $mydomain
smtpd_sender_restrictions = 
hash:/etc/postfix/access,reject_unknown_sender_domain
smtpd_use_tls = no
strict_rfc821_envelopes = yes
transport_maps = hash:/etc/postfix/transport
unknown_local_recipient_reject_code = 550
virtual_alias_domains = hash:/etc/postfix/virtual_domains
virtual_alias_maps = hash:/etc/postfix/virtual


Forma de mandar desde php:

//script
<?php
$para      = 'miname en midomain.com';
$asunto    = 'el asunto';
$mensaje   = 'hola carabola';
$cabeceras = 'From: miname <miname en midomain.com>' . "\n" .
    'Reply-To: miname en midomain.com' . "\n" .
    'X-Mailer: PHP/' . phpversion()."\n";

mail($para, $asunto, $mensaje, $cabeceras, '-fminame en midomain.com');
?>

or using this:


/* recipients */
$to  = "info en MI_DOMINIO.com"; //$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);
?>