This is very WIP. Since i started doing this, i was mostly aiming for a server that didn't crash. It can load plugins, commands work, lots of things work, permissions should work, etc.
Most of this mod is a fairly straight port from Craftbukkit, but I've had to modify parts (and i anticipate modifiying more).
This is ported to 1.4, and works fine on 1.4.5
That's right, now we have an automated jenkins build-thingy. You may find it here
After unzipping the forge source, copy bukkit_at.cfg to forge/accesstransformers (create the folder if it's not there), and copy all the files in 'lib/' (excluding bukkitAPI.jar) into the lib folder in mcp. decompile as usual. You will also need to add the files in the 'lib' folder (excluding bukkitAPI.jar) into the projects in eclipse.
You need Apache Ant and the JDK. To build, run 'git submodule sync' in the root folder, and then cd to the 'blockbreak' folder and type 'git pull origin'. cd back up one level and simply type 'ant' in the folder with build.xml inside it.
If your mod does NOT use guava, you're fine, it should work.
If your mod DOES use guava, you need to add 'guava10' before all of your guava imports. The reason this is required is FML uses guava 12 which is not compatible with guava 10. So BukkitForge ships with guava 10 in 'guava10.com.google.xxx' rather than 'com.google.xxx'.
Speak english, and please, report it in issues!
This mod is licensed under the LGPL, the same as Craftbukkit.