We'll be working on deployment next year that is not tied to specific versions of drools. The reason for this is that the Packge is really just a cached form representing the DRL, to avoid compiling drls on the client. We actually just serialise the resulting objects. But internally we do a lot of changes as we add features, so binary compatability of these cached objects is not easily and cheapily possible.
In the future we hope to produec a simpler intermediary format that will be durable across different versions of drools. It will require the clients to do a bit more work, as it won't be as cheap as serialisation. But we hope that it'll be an acceptable trade off.