I also got this error during a wordpress installation on remote server.
Anyways, lets cut to the chase: I found that the remote server i was trying to install Mailpress on runs on PHP version 4.4.7 and MailPress.php actually needs at least PHP version 5 because of the use of a public static function on line 118(MailPress.php) PHP versions below 5 uses var instead.
You can check what PHP version you’re running by the help of the PHP test <?php
phpinfo();
?>
Hope this helps (it did help me:-)
