function setZero(id){
var myEls = getElementsByClass(id);

	for ( i=0;i<myEls.length;i++ ) {
		myEls[i].style.opacity = "0"
	}
}
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++;
		}
	}
	

	
}
function changeOpac(opacity, id) {

	var myEls = getElementsByClass(id);

	for ( i=0;i<myEls.length;i++ ) {
		myEls[i].style.opacity = (opacity / 100);
		myEls[i].style.MozOpacity = (opacity / 100);
		myEls[i].style.KhtmlOpacity = (opacity / 100);
	}
}

function getElementsByClass(searchClass,node,tag) {
	var classElements = new Array();
	if ( node == null )
		node = document;
	if ( tag == null )
		tag = '*';
	var els = node.getElementsByTagName(tag);
	var elsLen = els.length;
	var pattern = new RegExp("(^|\\s)"+searchClass+"(\\s|$)");
	for (i = 0, j = 0; i < elsLen; i++) {
		if ( pattern.test(els[i].className) ) {
			classElements[j] = els[i];
			j++;
		}
	}
	return classElements;
}