Very nice one! You can try to upload the jar file using [b]Upload new EJS jar file.[/b] options when you edit the message.
There is a checkbox right after "spell check", click the checkbox,
and you will upload file buttons.
Select the jar file and click "Post" buton to save the message as usual.
In this way, the uploaded jar file will be used to display the created simulation.
An applet will be shown at the end of the posted message.
If it is the first message and you also attached a gif/jpeg file as attached file (you can generated it with created simulation. Just right click and select [b]snapshot[/b] in the simulation region, and save it.
Please try it next time.