Form exit in MV45AFZB.

Hi,

My requirement is the users need to validate documents created in the SD module to ensure that the correct CO object is used before the document is transferred to FI i.e. for particular company code if my G/L account number is starting with 4 then I should not pass the WBS element to G/L account and pop up a error msg, the error msg will be created in se91.

Now in which form exit I can use for this? or if i need to write my own form exit then where can i write my code?

This form exit which i should modify or create will be then assigned to a validation rule through tcode OB28

can any one help me with this?

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