excise capturing for sto

dear all

i am doing sto for excisable material. chapter id is maintained .( all J1id pre requisite maintained) My requirement is to capture excise components which is not appearing as of now. I follow the process as below:

me21n

vl10b

vf01 ( excise proforma invoive -biling type)

j1iin( to capture excise components.

what is the customization to be done .do i need to maintain different calculation schema for this?pls guide me with all the relevent customizations to achive this pls...

thanks

shankar