function init() {
	// adjust the main div height if necessary
    var sidebar = document.getElementById("sidebar");
    var main = document.getElementById("main");
    
    var mainHeight = getHeight(main);
    var sidebarHeight = getHeight(sidebar);
    if (navigator.userAgent.toLowerCase().indexOf("msie") > -1) {
	    sidebarHeight += 30;
	}
    //if (sidebarHeight > mainHeight) {
    //    sidebar.style.height = mainHeight + "px";
    //}
	if (mainHeight < sidebarHeight) {
        main.style.height = sidebarHeight + "px";
    }
}

function getHeight(elem) {
    var height = Number.NaN;
    var offset = 40;
    if (elem != null) {
        if (window.getComputedStyle) {
            height = window.getComputedStyle(elem, null).height;
            var pxIndex = height.indexOf("px");
            if (pxIndex >= 0) {
                height = Number(height.substr(0, pxIndex));
            }
			var uaString = navigator.userAgent.toLowerCase();
            if (uaString.indexOf("opera") > -1) {
                height -= offset;
            }
        } else {
            height = elem.clientHeight - offset;
        }
    }
    return height;
}

if (window.addEventListener) {
    window.addEventListener("load", init, false);
} else if (window.attachEvent) {
    window.attachEvent("onload", init);
} else {
    window.onload = init;
}