var imgListLen = 5;
var imgName = new Array(imgListLen);
imgName[0] = 'AspenBuildBckGrnd.jpg';
imgName[1] = 'AspenBuildBckGrnd2.jpg';
imgName[2] = 'AspenBuildBckGrnd3.jpg';
imgName[3] = 'AspenBuildBckGrnd4.jpg';
imgName[4] = 'AspenBuildBckGrnd5.jpg';

setInterval('reloadImage()', 15000); // 15 seconds
function reloadImage()
{
	var bg = document.getElementById('bdy');
	bg.background = '/images/' + imgName[setBgImage(imgListLen)] //+ '?' + Math.random();
}
function setBgImage(range) {
	if (Math.random) {
		return Math.round(Math.random() * (range-1));
	} else {
		var now = new Date();
		return (now.getTime() / 1000) % range;
	}
}