var RegEmail   = new RegExp ("^[a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z]{2,5}$");

function verifier(frm)
{
  if(frm.elements['chp_nom'].value != "" && frm.elements['chp_prenom'].value != "" && frm.elements['chp_email'].value != "" && frm.elements['chp_objet'].value != "" && frm.elements['chp_message'].value != "")
  {
		if(RegEmail.test(frm.elements['chp_email'].value))
		{
			return true;
		}
		else
		{
			alert("'Email' is not a valid format !");
			frm.elements['chp_email'].focus();
			return false;
		}
	}
	else
	{
		alert("Please fill in all the fields !");
		frm.elements['chp_nom'].focus();
		return false;
	}
}