Adding an option to configure the hostname in HELO when sending emails from Postfix Admin

config.inc.php

@@ -125,6 +125,11 @@ $CONF['admin_email'] = '';
 $CONF['smtp_server'] = 'localhost';
 $CONF['smtp_port'] = '25';
 
+// SMTP Client
+// Hostname (FQDN) of the server hosting Postfix Admin
+// Used in the HELO when sending emails from Postfix Admin
+$CONF['smtp_client'] = 'localhost.localdomain';
+
 // Encrypt
 // In what way do you want the passwords to be crypted?
 // md5crypt = internal postfix admin md5

functions.inc.php

@@ -1136,7 +1136,7 @@ function smtp_mail ($to, $from, $data, $body = "") {
     $smtpd_server = $CONF['smtp_server'];
     $smtpd_port = $CONF['smtp_port'];
     //$smtp_server = $_SERVER["SERVER_NAME"];
-    $smtp_server = php_uname("n");
+    $smtp_server = $CONF['smtp_client'];
     $errno = "0";
     $errstr = "0";
     $timeout = "30";