Jar and Jad files

The java applications that you can send to your phone are either .jad or .jar, jad is prefered, but if you don't have a file of this type you can use JADMaker to convert a jar.

Before you can install the new software you will need to ensure that the Java Applet Loader on your phone is enabled, excellent instructions for this can be found in this thread at Howardforums.