Somewhere between your browser and RAF's server (in Houston, Texas, if I recall correctly) there's an intercepting cache. It's intercepting the request for Male.gif and Female.gif, and responding with a previously-downloaded copy.
Normally, Shift + F5 in both IE and Firefox sends a "cache-control: no-cache" header, which according to the HTTP standard, "MUST" be sent to RAF's server for a fresh response.
Apparently, someone decided that saving bandwidth is more important than following the agreed-upon standard. This is probably happening before the request is sent on one of the crowded undersea cables that handle continent-to-continent communications.
That would explains why this issue doesn't seem to affect American or Canadian users--they don't need to use an undersea cable, but can just hop on the fairly-good North American network.
Still, you do have grounds to complain. You're paying for Internet service (probably by the byte in Australia, from what I've heard), yet you're getting substandard service.
