[rules-users] How to add rules to working memory during livetime?

Hi, I want to add a new rule to an existing workingmemory. I not want to loose the "situation" in this workingmemory. First I create a new workingmemory and insert a couple of facts. After firingAllRules it could be possible to add some new rules (load some new drl-files) to the existing workingmemory without loosing the facts inside this. Is this possible? First idea was to retrieve all facts from the workingmemory, create a new one including the new rules and insert all facts again? Is this the correct way? Thanks Thorsten