how to model GL document splitting with GL lin item in BW?

Hi

For Line Item wise GL reporting SAP offers 2 DataSources

1) 0FI_GL_4

2) 0FI_GL_14

but non of the above datasources offer document splitting info or no datasource available on

document splitting table FAGL_SPLINFO.

So how can I develop BW model for GL document splitting with GL lin item in BW?