I heard several times that it's not quite clear what is the difference between JT harness and ME Framework. Yesterday one good analogy crossed my mind.

Imagine that you have a media player which has a pluggable architecture. It means that you can extend the base functionality of the player with a set of plug-ins. New video or audio format, new rendering types... No problem. All you need is to install the corresponding plug-in. Even if there is no such plug-in - you can create it by yourself.

JT Harness is exactly corresponding to such media player. It's a general test harness which doesn't know anything about Java ME specific requirements. At the same time ME Framework can be considered as a set of plug-ins to enable effective testing of Java ME stack. It contains the support of Java ME specific tests and features and allows you to quickly create test suite for Java ME stack.