function check(obj) {
  err = false;
  val = obj.value;
	
  if (val == '' || val == '-' || val == 'http://')
    err = true;

  if(err == false) {
    if (obj.name == 'email' && 
      (val.indexOf('@') < 1 || val.indexOf('@') == (val.length - 1)))
        err = true;
  }

// Change class
  if (err) 
    obj.className='formerror';
  else
    obj.className='flat';
  
  return(err);
}

function change(ort) {
  if(document.forms[0].von.value!=ort) {
    document.forms[0].nach.value=ort;
    document.forms[0].nach_dis.value=ort;
    document.forms[0].nach.disabled = true;
    document.forms[0].nach.style.background = '#c0c0c0';
  } else {
    document.forms[0].nach.value=document.forms[0].nach.defaultValue;
    document.forms[0].nach.disabled = false;
    document.forms[0].nach.style.background = '#ffffff';
    document.forms[0].nach.value='';    
  }
}