function checkEmail(a_mail) 
{
	mymail 				= a_mail;
	var mail_err 	= 0
	var r_mail 		=  /^([a-z0-9]+([a-z0-9-_]+)*\.)*[a-z0-9]+([-_]?[a-z0-9]+)*@([a-z0-9]+([-_]?[a-z0-9]+)*\.)+[a-z]{2,4}$/
	ok_mail 			= r_mail.exec(mymail);
	
	if (!ok_mail) {
		//alert("false");
		return false;
	} 
	else 
	{
		//alert("true");
		return true;
	}
}

/*
function checkEmail(a_mail) {
   mymail = a_mail;
   var mail_err = 0
   var r_mail =  /^([a-z0-9]+([a-z0-9-_]+)*\.)*[a-z0-9]+([-_]?[a-z0-9]+)*@([a-z0-9]+([-_]?[a-z0-9]+)*\.)+[a-z]{2,4}$/
   ok_mail = r_mail.exec(mymail);
   if (!ok_mail) {
   	  //alert("false");
      return false;
   } else {
   	  //alert("true");
      return true;
   }
}

function checkEmail0(a_mail) {
   mymail = a_mail;
   var mail_err = 0
   var r_mail =  /^([A-Za-z0-9]+([A-Za-z0-9-_]+)*\.)*[A-Za-z0-9]+([-_]?[A-Za-z0-9]+)*@([A-Za-z0-9]+([-_]?[A-Za-z0-9]+)*\.)+[A-Za-z]{2,4}$/
   ok_mail = r_mail.exec(mymail);
   if (!ok_mail) {
   	  alert("false");
      return false;
   } else {
   	  alert("true");
      return true;
   }
}

function verif_mail2(a_mail) {
   mymail = a_mail;
   var mail_err = 0
   var r_mail = /^[A-Za-z0-9._-]+@[A-Za-z0-9.-]{2,}[.][A-Za-z]{2,4}$/
   ok_mail = r_mail.exec(mymail);
   if (!ok_mail) {
   	  alert("false");
      return false;
   } else {
   	  alert("true");
      return true;
   }
}
*/