LEJOS_HOME is only used for the RCX version. In 0.3 or 0.4 of NXJ it was changed to NXJ_HOME which allows you to be able to program for both platforms with no issues. i currently use both with no problems. I'm not using any plugins in eclipse since the RCX plugin does not work in Linux. and i have not bothered to try the NXJ plug in since compiling and uploading from a term is no big deal for me.