<script language="JavaScript">
if(screen.width == 800)
window.location.href = "index800.html"
else if(screen.width == 1024)
window.location.href = "index1024.html"
else if(screen.width >= 1152)
window.location.href = "index+.html"
else if(screen.width == 640)
window.location.href = "index640.html"
</script>
wenn du diesen script vielleicht umschreibst...