I would recommend not using jBPM4 as it is a dead project. There is no development against it, and also RedHat does not support jBPM4. Best for you is to use jBPM5, and if for some reason you cannot, you should is jBPM3 because even tho there is no more new development done for it, at least you can still get support for it from RedHat.
Hope this helps.