i300/i320 Java Installer
It's free and, what's better, it functions. I tested it to install Opera mini (latest version) and a game named Dr. eiDRuC (a 3D version of the the Rubik cube).
Instructions (taken from the site indicated above):
To use it, you should associate .JAR files with it (you can use Smart Explorer or Resco Explorer to do it).
Then just launch a JAR file from your favourite filemanager.
Or you can simply execute it without any parameters and press "OK".
If you'd have problems to install it or to associate the file to the program, let me know and I'll explain how I did it.
Edited by derma, 10 May 2007 - 10:05 PM.