I have JWPce. It's useful for me sometimes. But I don't know if it will satisfy all your needs.

jim breen in google.

Then you want JWPce.  You can download it here.

There is 2 Dictonnaries that came out on nintendo DS.
avoid the first one, take the second one (with the little rainbow on the cover).
I use it everytime and it's very complete. It's the best dictionnary I have.
It was made for japanese peoples, but it's still very usefull if you are a japanese learner.
If you have no japanese knowledge, it could be hard to use.
It's not as god as a real electronic dictionary, but it's largely cheaper.

You can buy this card on any game import sites.
http://www.youtube.com/watch?v=88ziFTPpHxE&feature=related

Well as it turns out the Japanese Microsoft IME has an excellent stroke recognition system.

So good in fact, that I don't need anything else.

JQuick trans is also a very useful tool.