function sendMail()
{ 
	var url='';
	var data = '';

	if (document.contact.email.value.length == 0)
	{
		alert("Veuillez renseigner votre email." );
	} 
	else
	{
		url="ajax/sendMail.php";
		
		data="email="+document.contact.email.value+"&subject="+document.contact.ask.options[document.contact.ask.selectedIndex].innerHTML+"&msg="+document.contact.msg.value;
		
		var xhr=GetXmlHttpObject();
		//on définit l'appel de la fonction au retour serveur
		xhr.onreadystatechange = function() { if (xhr.readyState==4 || xhr.readyState=="complete") { alert (xhr.responseText); }};
		xhr.open("POST",url,true);
		xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
		xhr.send(data);
	}
}