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 + ")"; 
}