Valuation price change in PR - User Exit

Question

Hello all,
In Purchase Requisition valuation tab there is the field BPUEB (PO Price EBAN-BPUEB) that is used to transfer the valuation price from the PR to the PO.
The field's values are :
0. Do not adopt
1. As gross price
2. As net price
The default value is "Do not adopt".
How can I change the default value to "As net price" ?
I am looking for a user exit, because i need to do some condition check before i change this to "As net price".
Pl suggest.
Thanks

Answer 1

Solved Myself.
Solution:
Exit : EXIT_SAPLMEREQ_005
Include : ZXM02U05
Code:
FIELD-SYMBOLS: <IS_ACC> TYPE LINE OF MMPUR_ACCOUNTING_LIST.
DATA : ACCOUNTING_LIST TYPE MMPUR_ACCOUNTING_LIST.
DATA : RE_EXKN TYPE EXKN.
DATA : L_AUART TYPE VBAK-AUART.
DATA : L_PSTYV TYPE VBAP-PSTYV.
  CLEAR RE_EXKN.
  ACCOUNTING_LIST = IM_REQ_ITEM->IF_ACCT_CONTAINER_MM~GET_ITEMS( ).
  LOOP AT ACCOUNTING_LIST ASSIGNING <IS_ACC>.
    CALL METHOD <IS_ACC>-MODEL->GET_EXKN
    RECEIVING
    RE_EXKN = RE_EXKN.
  ENDLOOP.
  CLEAR : L_AUART, L_PSTYV.
  SELECT SINGLE AUART FROM VBAK INTO L_AUART
                         WHERE VBELN = RE_EXKN-VBELN.
  SELECT SINGLE PSTYV FROM VBAP INTO L_PSTYV
                         WHERE VBELN = RE_EXKN-VBELN
                           AND POSNR = RE_EXKN-VBELP.
  IF SY-TCODE = 'ME51N' AND L_AUART = 'ZMO' AND L_PSTYV = 'ZTAB'.
    LS_MEREQ_ITEM-BPUEB = '2'.  "AS NET PRICE - PO Price field
  ENDIF.
Thanks,
Senthil