function champsok(radio)
{

for (var i=0; i<radio.length;i++) {

         if (radio[i].checked) {
		 	 if (radio[i].value == 1) {
				if (document.form.email.value.length == 0){alert("Indiquez un email");return false;}
			}
			 if (radio[i].value == 2) {
				if (document.form.telephone.value.length == 0){alert("Indiquez un téléphone");return false;}
			}
         }
}
return true;
}