BADI : for change split logic of billing document

Hi Experts,

I have requirement for adding logic for split criteria in Billing Document.

I have added a custom field in billing due list , my requirement is to change spilt logic

of billing document  based on that custom field value.

Is this badi : /BEA/BDCPREQ help ?

How to add spiting criteria based on custom field .

Pls suggest me .

Thanks in advance.

Regards

Alok