Does CSTPSCHK will allow to account generation / updation by sub-element ? Please review..

Hello all
Greetings.
1. Does CSTPSCHK allow UPDATING default account by sub element ?
I used CSTPSCHK.std_get_account_id to update default account by element ID. My new requirement is to update account by Sub element ID also.
Here is example:
Cost-element Sub-cost-element
Material         OverHead Duty

Lets say item T2X have cost as follows:
Cost-element Sub-cost-element
Material -1 Material Default account - 1222  new account 6666
MOH-2       Duty       Default account - 1333 new account 7777

How do I use cost extension to allow to use sub-cost-element also along with cost element to update the account ?
I was able to do it at cost element ID level. In the above example, I want to use MOH (cost element ID -2) and also the Sub-cost-element Duty to change the account from 1333 to 7777.