401K Limit for different Ages (Urgent)

Hi,

We have a following requirement.

For employees with AGE >=50 , the 401K Employee Pre Tax limit should be $20,500 and For employees with AGE < 50 , the 401K Employee Pre Tax limit should be $15,500.

Note : We do not need any CATCHUP limit to be configured in our system. From 2008, the employees won't have Catch Up contribution.

I see, that in T511P ( Molga = 10 , KONST = 401KL ,Begda = 01/01/2008) , the amount defined is $15,500, which has been declared by the SAP. We need this amount for employees below age 50. But for employees with AGE >=50 we need to put the 401K Amount to $20,500.

Please let me know, how can we achieve this functionality.

Points will be awarded for relevant suggestion too.

Regards,

Anirban