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 {
        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 {
        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();
        }
    }
}