Business Area not filled in some line item postings

Hi dear SAP Gurus,

I am currently implementing a new company and, like the others from the group (wich are on different SAP systems), the customer wants to have all line items filled with the Business Area.

However, that is not happening, for example, for manual bank statements or tax line items (automatically generated, of course).

We have "Business Area Finantial Statements" option activated in OB65 / OBY6 and, besides that, we have a substitution (like in the other customers, which is the only thing I think it's populating the field) that, when BSEG-BUKRS = "XXXX", BSEG-GSBER = "0004".

We are currently on EHP7 for SAP ERP 6.0. SAP_APPL and SAP_FIN are both on 617 SP3 release. I have already searched for notes, but didn't find anything similar.

Any thoughts?

Thanks in advance!

AB.