The <object onload>
attribute works well in latest versions of Firefox, Chrome and Opera (I’ve just tested it).
Also, the expression 'onload' in document.createElement('object')
evaluates to true
in Chrome and Opera; naturally, Firefox is an exception because such event support check doesn’t work there generally. kangax describes cross-browser event support detection at http://perfectionkills.com/detecting-event-support-without-browser-sniffing/