function valid_email(mail){
validRegExp = /^[\w-.]{1,}@[\w-.]{1,}\.\w{2,}$/i;
     if (mail.search(validRegExp) == -1) 
   {
     document.contact.subject.disabled=true;
     document.contact.subject.className="textinak";
     document.contact.body.disabled=true;
     document.contact.body.className="textinak";
     document.contact.replyto.focus();
   } else {
     document.contact.subject.disabled=false;
     document.contact.subject.className="textakti";
   } 
}

function valid_subject(subject){
validRegExp = /^[\w .]{5,}/i;
     if (subject.search(validRegExp) == -1) 
   {
     document.contact.body.disabled=true;
     document.contact.body.className="textinak";
     document.contact.Abschicken.disabled=true;
   } else {
     document.contact.body.disabled=false;
     document.contact.body.className="textakti";
   }
}

function valid_body(body){
validRegExp = /[\w-.]*/i;
     if (body.search(validRegExp) == -1) 
   {
     alert('Zeichen nicht erlaubt.');
   }
}

function form_reset(){
document.contact.subject.disabled=true;
document.contact.subject.className="textinak";
document.contact.body.disabled=true;
document.contact.body.className="textinak";
document.contact.replyto.focus();
}