Salut,
<head>
<script type="text/javascript">
function ouvre(site1,site2)
{
window.open(site1, "site1", "height=500,width=500,scrollbars=1");
window.open(site2, "site2", "height=500,width=500,scrollbars=1");
}
</script>
</head>
<body onLoad="ouvre('http://www.google.fr','http://www.voila.fr')">
</body>
@++