function verif(email) {
     var reg = /^[A-Za-z0-9\-_.]+@[A-Za-z0-9\-_.]{2,}[.][a-z]{2,4}$/
     
     if(reg.exec(email)==null) return false
     return true
}
function verifemail(mail) {

	
   	if(!verif(mail.value)) { alert('E-mail invalide !');mail.focus();return false }
	
	return true
}