No, it has nothing to do with Raven. Raven wants to release it, but they cannot. First of all, id's engine source code is tied in with the singleplayer source code, so they may have to release id's Quake III Team Arena source code with it, which id won't let happen. Second, LEC won't let Raven. Several of Raven's programmers have been pushing LEC to allow them to release various things for singleplayer editing. Maybe it means the sourcecode, maybe it doesn't. It's possible they figured out a way to let us mod more stuff without giving out id's precious Q3TA source.
Besides, with JA's new SP and MP modding capabilities which we'll have our hands on in about five months, there's no real point in bothering with the JO source code. JO projects can be easily ported to JA.
It's really nice when people research things before they post. Too bad we don't see any of that around here.