Preventing cache on back-button in Safari 5

The empty unload handler will not work anymore. Instead you can check the persisted property of the onpageshow event. It is set to false on initial page load. When page is loaded from bfcache it is set to true.

Kludgish solution is to force a reload when page is loaded from bfcache.

window.onpageshow = function(event) {
    if (event.persisted) {
        window.location.reload() 
    }
};

If you are using jQuery then do:

$(window).bind("pageshow", function(event) {
    if (event.originalEvent.persisted) {
        window.location.reload() 
    }
});