I have explored this issue quite a bit several months back and have determined that there is no effective way to create a cross browser rmi application. For instance, you could use signed
applets and then set the client jvm permissions to allow the rmi connections but then you end up using the microsoft implementation of the jvm. the last time I checked, Explorer does not support rmi. So, you could use the Object <EMBED> tags to force the browser to use Sun's appletviewer. This work fairly well, since is runs outside the browser and, therefore, is not as restricted as a jvm running from within. Again, the issue here is that Apple has not ported a version of the applet viewer (even though they announced support '98 - maybe os X). Another option is to create a desktop application that clients can download - this relieves you of a lot of the security issues but reduces the effectiveness of the application since it has to be trusted and downloaded. Ultimately, I skirted the rmi approach altogether and wrote my application using sockets. If you only want to support a single browser/platform, then you do have options, however. If anyone has another solution, it would be great to here it.
Sean