Leave quota generation regarding grades

Hi we are using leave quota generation regarding senority and employee grade.

We use feature QUOMO to set different generation rule for different grades.

If EE seniority is changed during the year entitlement is calculate correctly.

But if grade is changed during the year entitlement is set regarding grade valid at the begining of the year.

Example: Grade N entitlement 22 days, Grade M enitlement 24 days.

IF ee has grade N 1.1.2010 he gets 22 days, if he has grade M 1.1.2010 he gets 24 days.

But if employee change grade on 1.6.2010 from N to M default value for leave entitlement is not changed.

Any suggestions please?

Thanks

Dasa