I sometimes have trouble getting into chat... (the browser says 'applet started', but the applet never loads)

I was thinking this was due to my corporate firewall, but sometimes I can get into chat on the same computer, on the same network connection.

When I can't get in, retrying doesn't seem to help. And when I can get in, I usually can do so on the first try.

I have tried clearing my cache, clearing my cookies, and rebooting, but it seems like access to chat is a crapshoot.

Anyone have any suggestions?