How are your clients handling employer's contributions to 401K where there is a cap? For example, employer contributes 25% of 401K up to 6% of gross. Employee has 100.00 fixed amount of 401K each week. If they work few hours, that is more than 6%. If they work a full 40, it's less. Or employee has 8% 401K. Can't just use the std 25% of 401K because of the 6% cap.