Gregor, I used to get such mails all the time about AquaLime. You are right, many people have no clue about java.

To fix it,I packaged it in an executable installer, that put optional shortcuts on the desktop and in the start menu. This way the users do not have to know about java at all, but there are still no executables used to launch it. (for me, having an .exe installer was bad enough, using them to launch the program seems weird)