If a rule (event) has the following:
+ "when\n"
+ " $s : Cheese(type==\"stinky\")\n"
+ " not( Cheese(type==\"a\", this after [0s,3s] $s ) )\n"
+ " not( Cheese(type==\"b\", this after [0s,5s] $s ) )\n" //2 * not

and pseudo clock is used, the rule doesn't fire.
If realtime clock is used, the rule works.