//Reference http://brainerror.net/scripts/javascript/blendtrans/
function Opacity(id, opacStart, opacEnd, millisec) {
    //speed for each frame
    var speed = Math.round(millisec / 100);
    var timer = 0;

    //determine the direction for the blending, if start and end are the same nothing happens
    if(opacStart > opacEnd) {
        for(i = opacStart; i >= opacEnd; i--) {
            setTimeout("ChangeOpac(" + i + ",'" + id + "')", (timer * speed));
            timer++;
        }
    } else if(opacStart < opacEnd) {
        for(i = opacStart; i <= opacEnd; i++){
            setTimeout("ChangeOpac(" + i + ",'" + id + "')", (timer * speed));
            timer++;
        }
    }
}

//change the opacity for different browsers
function ChangeOpac(opacity, id) {
    var object = document.getElementById(id).style;
    object.opacity = (opacity / 100);
    object.MozOpacity = (opacity / 100);
    object.KhtmlOpacity = (opacity / 100);
    object.filter = "alpha(opacity=" + opacity + ")";
}