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 + ")"; 
} 

function pause_interval()
{
    clearTimeout(timeout[3]);
	now = new Date();
	now = now.getTime();
}
	
function continue_interval()
{
    time_left_difference = now-timeout[0];
	time_left = timeout[2]-time_left_difference;
	
	timeout[3]=setTimeout(timeout[1],time_left);
	
	now_new = new Date();
	now_new = now_new.getTime();
	timeout[0]=now_new-time_left_difference;
}