function colheight(containerId, tags) {
	if (tags == null) {
		tags = ['div'];
	}
	
	colheight.processIds = function() {
		for (var i = 0; i < colheight.ids.length; i++) {
			var id = colheight.ids[i];
			var el = document.getElementById(id.containerId);
			if (!el) continue;
			
			var max = -1;
			for(var j = 0; j < el.childNodes.length; j++) {
				var chld = el.childNodes[j];
				if (!chld.tagName) continue;
				if (id.tags[chld.tagName.toLowerCase()] !== true) continue;
				if (chld.offsetHeight > max) {
					max = chld.offsetHeight;
				}
			}
			for(var j = 0; j < el.childNodes.length; j++) {
				var chld = el.childNodes[j];
				if (!chld.tagName) continue;
				if (id.tags[chld.tagName.toLowerCase()] !== true) continue;
				if (chld.offsetHeight < max) {
					chld.style.height = max + 'px';
					if (chld.offsetHeight > max) {
						var diff = chld.offsetHeight - max;
						chld.style.height = (max-diff) + 'px';
					}
				}
			}
		}
	}
	
	if (document.addEventListener) {
		colheight.addEvent = function(el,event,handler){
			el.addEventListener(event, handler, false);
		}
	} else if (document.attachEvent) {
		colheight.addEvent = function(el,event,handler){
			el.attachEvent('on' + event, handler);
		}
	}

	if (!colheight.onloadAttached) {
		colheight.addEvent(window, 'load', function() {
			setInterval(function() {
				colheight.processIds();
			}, 10);
		});
		colheight.onloadAttached = true;
	}
	
	colheight.ids = colheight.ids || [];
	var atags = {};
	for (var a = 0; a < tags.length; a++) {
		atags[tags[a].toLowerCase()] = true;
	}
	colheight.ids.push({'containerId':containerId, 'tags':atags});
}