Add dkim support (Patch by Florian).

tbrehm

2013-04-19 56f69880ecab67ba23df54aa849d7f4e1d600da8

 interface/web/admin/form/server_config.tform.php

@@ -211,6 +211,19 @@
         'width' => '40',
         'maxlength' => '255'
      ),
                'dkim_path' => array(
                        'datatype' => 'VARCHAR',
                        'formtype' => 'TEXT',
                        'default' => '/var/db/dkim',
                        'validators'    => array (  0 => array ('type'  => 'CUSTOM',
                                                                'class' => 'validate_dkim',
                                                                'function' => 'check_dkim_path',
                                                                'errmsg'=> 'dkim_path_error'),
                                                 ),
                        'value' => '',
                        'width' => '40',
                        'maxlength' => '255'
                ),
      'pop3_imap_daemon' => array(
         'datatype' => 'VARCHAR',
         'formtype' => 'SELECT',