try{
    xmlhttp = new XMLHttpRequest();
}catch(ee){
    try{
        xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    }catch(e){
        try{
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }catch(E){
            xmlhttp = false;
        }
    }
};

atual=0

function link_hit(id_link){ 
	var id    = id_link;
	var post  = 'id='+id;

	xmlhttp.open("POST","clientes.php?banco=link_hit",true);
	xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
	xmlhttp.send(post);
    xmlhttp.onreadystatechange=function() {
        if (xmlhttp.readyState==4){
			//alert(xmlhttp.responseText)
        }
    }
};