Ntt Docomo just opened a website dedicated to Doja (oversea) developpement.
http://www.doja-developer.net/
It’s quite well executed actually, you can found:
- Forum
- Articles
- Tips
- Support
- Handsets informations (jar, jam, scratchpad, heap, screensize, user agents etc…)
- And last but not least, there are the emulators for Doja v1.5 and v2.5 (3D!)
There is a “give us a full java emulator” thread in the forum, I strongly suggest Unix & Mac OS X users to participate (and windows fellow too) 
Have a nice time,
Fraggle