function getElementsByClass(searchClass,node,tag) {
// by dustin diaz
// http://www.dustindiaz.com/getelementsbyclass

	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;

}

function setOpacity(obj, opacity) {
	opacity = (opacity == 100)?99.999:opacity;
	
	// IE/Win
	obj.style.filter = "alpha(opacity:"+opacity+")";
	
	// Safari<1.2, Konqueror
	obj.style.KHTMLOpacity = opacity/100;
	
	// Older Mozilla and Firefox
	obj.style.MozOpacity = opacity/100;
	
	// Safari 1.2, newer Firefox and Mozilla, CSS3
	obj.style.opacity = opacity/100;
}