[rules-users] Drools in multithreaded env

[Jin]

Env setup:
1. There is only one instance of working memory.
2. There are at lease two threads constantly insert/update/delete facts from the
same workings memory based on some incoming messages.
3. I use temporal rules (duration clause) as well. When it is fired, it will be
on the third thread.

Question:
I can synchronize the first two threads by acquiring lock on the working memory.
But how do I synchronize the temporal rules thread especially on the left hand
side of the rules? 


Thanks,
Jin