The issue isn't with jansson, it's with libblkmaker. It seems you have the normal (i.e. non-primecoin) version. You have to download libblkmaker from https://dl.dropboxusercontent.com/u/55025350/bitcoin-libblkmaker.zip. It is the libblkmaker prime branch, with a couple of primecoin-specific things added. Those auxdata parameters are important, without them the miner won't work.