function change_class(_b) {
	document.getElementById("quisommes").className="quisommes";
	document.getElementById("newslettre").className="newslettre";
	document.getElementById("annances").className="annances";
	
var btn = document.getElementById(_b);
btn.className=_b+"_h";
} 

function rollover_tjs(nom,src) {
		document.images[nom].src=src;
		document.getElementById("lien_g").href=src;
	}