<script type="text/javascript">

    // 'load' events should be supported by every browser
    // this was just an exercise to find a way to test it

    var isLoadSupported = 'onload' in window, loadHandler = window.onload;
    document.createElement('body').setAttribute('onload', 'return');
    isLoadSupported = isLoadSupported || typeof window.onload == 'function';
    window.onload = loadHandler;

    window.addEventListener('DOMContentLoaded', function(e) {
        alert(e.type + " - " + isLoadSupported);
    }, false);

    window.addEventListener('load', function(e) {
        alert(e.type + " - " + isLoadSupported);
    }, false);
</script>