javascript: capturing load event on LINK

i’m trying to attach an event handler to the load event of a link tag, to execute some code after a stylesheet has loaded.

new_element = document.createElement('link');
new_element.type = 'text/css';
new_element.rel = 'stylesheet';
new_element.href = 'http://domain.tld/file.css';
new_element.addEventListener('load', function() { alert('foo'); }, false);
document.getElementsByTagName('head')[0].appendChild(new_element)

i have tried onreadystatechange as well

new_element.onreadystatechange = function() { alert('foo'); }

unfortunately neither approach results in an alert being triggered..
Furthermore, new_element.onload is null after registering a handler for the ‘load’ event with addEventListener.. is that normal?

thanks,
andrew

ps: i may not use any framework in solving this