[rules-users] Stateful session and non-existence of Facts

Hi Guys, I have the following situation while running a stateful session with Drools 4.0.7: - I want to test that a fact with a given state doesn't exist; - It works fine - At a certain point I have to retract all facts and reinsert them at the stateful session - some of them actually changed and I don't want to recreate the session b/c it's expensive - Again the fact that didn't exist when I first created the session still doesn't exist ** Problem: This time the rule that verified the non-existence is not fired because I didn't insert any fact that would retrigger it. Rule example: rule "022" when SiteLanguage(language : languageCode) t : SiteSpecialServiceType(type : specialServiceType) not SiteLanguageSpecialServiceType(specialServiceType == type, languageCode == language) then <<consequence>> end How could I solve or workaround that? Thanks in advance, Leo.