function navOn(img) {
    var ext = img.src.substring(img.src.lastIndexOf("."));
    img.src = img.src.replace(ext, "On" + ext);
}

function navOff(img) {
    var ext = img.src.substring(img.src.lastIndexOf("."));
    img.src = img.src.replace("On" + ext, ext);
}


function disableSelection(target){
if (typeof target.onselectstart!="undefined") //IE route
	target.onselectstart=function(){return false}
else if (typeof target.style.MozUserSelect!="undefined") //Firefox route
	target.style.MozUserSelect="none"
else //All other route (ie: Opera)
	target.onmousedown=function(){return false}
target.style.cursor = "default"
}