Missing field between posted GR and MIRO

Question

Dear Experts,
     My company relate to ship management business. We open PO for clearing expense , no stock keeping .  So we customized new field name "Vessel Code" to manage expense for each vessel in account assignment tab when open PO. When post FI doc. transaction as below:
GR
          DR.      Expense   632XXXXX        vessel code
              CR.    GR/IR      252XXXXX
MIRO
         DR.      GR/IR          252XXXXX       vessel code
              CR.    Vendor     ABXXXX
My question, is it possible to copy vessel code to  "GR/IR   252XXXXX" when do GR step ? I assume that data when post FI doc. came from data in account assignment tab in PO. And vessel code field is customize field maybe I have to customize enhancement to copy or not ? Because user would like to analyze data by selection G/L 252XXXXX with vessel code in GR step.
Thank you.
Edited by: nasalapoa on Jun 8, 2010 11:55 AM

Answer 1

Dear Experts,
  As is : in accounting table BSEG there already have BSEG-ZVESSEL for updating date when post FI doc. from GR and MIRO . But when post FI doc at GR step , system only update in  BSEG-ZVESSEL (vessel copy from PO in account assignment tab) only in GL Expense . And copy to GL GR/IR when MIRO step
GR
DR. Expense     632XXXXX        vessel code
    CR. GR/IR       252XXXXX
MIRO
DR. GR/IR             252XXXXX             vessel code
      CR. Vendor     ABXXXX
To-be :  User would like to display vessel code in  "CR. GR/IR       252XXXXX" when post GR also . So my question, this relate to exit  that I have to create exit to copy vessel code to BSEG-ZVESSEL when post GR step with "CR. GR/IR       252XXXXX"
GR 
DR. Expense     632XXXXX              vessel code (already update in  BSEG-ZVESSEL )
                       CR. GR/IR       252XXXXX                  << to-be : need vessel code in BSEG-ZVESSEL .
Or are there any confiuration in standard system , I need to change?