function umschalten() {
          if(window.name == 'de') {
               location.href = 'http://www.rennertweb.de/index.html#reisen';
          }
          else if(window.name == 'en') {
               location.href = 'http://www.rennertweb.de/index-newzealand.html#reisen';
          }
          else {
               location.href = 'http://www.rennertweb.de/index.html';
          }
}