// Cross-browser implementation of element.addEventListener()



function listen(evnt, elem, func) {

    if (elem.addEventListener)  // W3C DOM

        elem.addEventListener(evnt,func,false);

    else if (elem.attachEvent) { // IE DOM

         var r = elem.attachEvent("on"+evnt, func);

    return r;

    }

    else window.alert('I\'m sorry Dave, I\'m afraid I can\'t do that.');

}



// Use: listen("event name", elem, func);