Screaming Penguin - Source Does Matter

As previously mentioned Carmack's J2ME development project An RPG Doom Game has it's site up with shots and info.

Frequently Asked Questions

Q: What phones or other platforms will it work on?

A: Doom RPG works on the mobile Java implementation J2ME with the MIDP 2.0 environment, and also on phones running BREW 2.0 or later. If your phone supports either of these platforms, there is a good chance you will be able to play Doom RPG on it. Visit jamdat.com to find out more.

Q: How will I be able to get Doom RPG on my phone?

A: The procedure for downloading a game to your phone varies among providers. Once the game is released, go to jamdat.com and follow their purchase instructions for your specific provider and handset.

Q: Will it have multiplayer?
A: No.