/*
 *  Überprüft die Email
 */
function checkEmailStr(s)
{
  var a = false;
  var res = false;
  if(typeof(RegExp) == 'function')
  {
   var b = new RegExp('abc');
   if(b.test('abc') == true)
     a = true;
  }

  if(a == true)
  {
   reg = new RegExp('^([a-zA-Z0-9\\-\\.\\_]+)'+'(\\@)([a-zA-Z0-9\\-\\.]+)'+'(\\.)([a-zA-Z]{2,4})$');
   res = (reg.test(s));
  }
  else
   res = (s.search('@') >= 1 && s.lastIndexOf('.') > s.search('@') && s.lastIndexOf('.') >= s.length-5)

  return(res);
}