I have a similar problem, I am trying to run an RMI application which was running fine locally using an appletviewer but due to some reason it does not run with a browser. It says "loading the applet" but doesn't show anything for a long time. If you were able to solve your problem then please do let me know how to go about it. I guess the reason might be due to the difference in versions of JDK provided by the browser and the applet.
Thanks in advance for any help..