function validNewsletter(){
var form=document.newsletter;
var email=form.mail.value;
var action=form.action;
var vtt=form.vtt;
var route=form.route;
var mailmsg="";
var actionmsg="";
var newsmsg="";
var validform="";
var i=0;

var email_Verif=email.indexOf("@",0);

if (email_Verif!=-1){
var emailPointVerif=email.indexOf(".",email_Verif);
}

if (email==""){
var mailmsg="- e-mail";
i++
}
if (email!=""&&email_Verif==-1||emailPointVerif==-1){
var mailmsg="- e-mail (adresse invalide)";
i++
}

if (action[0].checked==false&&action[1].checked==false)
{
var actionmsg = "\nInscrire / Désinscrire";
i++;


}

if (action[0].checked==true)
{
if (vtt.checked==false && route.checked==false)
{
var newsmsg = "\nVTT / Route";
i++;
}
}
if (i!=0)
{
validform="Les champs suivants ne sont pas remplis:\n-------------------------------------------------\n"+mailmsg+actionmsg+newsmsg;
window.alert(validform);
return false;	

}
else
{
return true;
}


}