anchor.diff:  
         extraDefaults = mkOption {
           default = "";
  +        type = types.lines;
           description = ''
             Will be inserted in the Default section of the config file.
           '';
  
positive.code: 
        portNumber = mkOption {
          default = 6667;
          description = ''
            Number of the port BitlBee will be listening to.
          '';
  
negative.code:       };
  
        interface = mkOption {
          type = types.str;
          default = "127.0.0.1";
          description = ''
            The interface the BitlBee deamon will be listening to.  If `127.0.0.1',
  