rule with accumulate(or collect) and no-loop recalculates as expected but not be fired

Issue

To calculate SUM of some facts, we are using the accumulate feature of Drools. and we found that the re-calculation in the accumulate condition happens after user update some facts, but that rule won't be fired. We tried "collect" instead of "accumulate", but it does not work neither.

When we comment out "no-loop true" and "update($target)", the rule is fired correctly, but that modification won't be propagated because it was not notified to the engine.

If we use "simple" conditions (without accumulate nor collect), it works fine.