// code by Danny Goodman, http://safari.oreilly.com/0596527403/orm9780596527402-CHP-VI

function addEvent(elem, evtType, func, capture) {
   capture = (capture) ? capture : false;
   if (elem.addEventListener) {
      elem.addEventListener(evtType, func, capture);
   } else if (elem.attachEvent) {
      elem.attachEvent("on" + evtType, func);
   } else {
      // for IE/Mac, NN4, and older
      elem["on" + evtType] = func;
   }
}

function removeEvent(elem, evtType, func, capture) {
   capture = (capture) ? capture : false;
   if (elem.removeEventListener) {
      elem.removeEventListener(evtType, func, capture);
   } else if (elem.attachEvent) {
      elem.detachEvent("on" + evtType, func);
   } else {
      // for IE/Mac, NN4, and older
      elem["on" + evtType] = null;
   }
}

function addOnLoadEvent(func) {
    if (window.addEventListener || window.attachEvent) {
        addEvent(window,"load", func, false);
    } else {
        var oldQueue = (window.onload) ? window.onload : function( ) {};
        window.onload = function( ) {
            oldQueue( );
            func( );
        }
    }
}