function validateMail(){

    if(document.mailform.naam.value==""){
        window.alert("Please fill in your name!");
		document.mailform.naam.focus();
        return false;
    }
	
	if(!document.mailform.email.value.match(/\b(^(\S+@).+((\.com)|(\.net)|(\.edu)|(\.mil)|(\.gov)|(\.org)|(\..{2,2}))$)\b/gi)){
        window.alert("Please fill in your valid e-mail address!");
		document.mailform.email.focus();
        return false;
    }
		
	if(document.mailform.onderwerp.value==""){
        window.alert("Please give a short description about your message in the subject field!");
		document.mailform.onderwerp.focus();
        return false;
    }

	 if(document.mailform.bericht.value==""){
        window.alert("Please write your message first!");
		document.mailform.bericht.focus();
        return false;
    }
    return ;
}