I have to change items of an Purchase Requisition before saving.
If I work with ME51N or ME52N I can change it easily with the method "PROCESS_ITEM" of BADI "ME_PROCESS_REQ_CUST", but when I convert a Planned Order into a Purchase Requisition via MD04 the method is not called.
Is there any other BADI, SMOD enhancement,... I can use?
Best regards Patrick
You might want to consider if the changes you are trying to make are in line with the best practice. When one document is created with reference to another then only very limited changes would be allowed. Otherwise the whole document flow could be broken. You'll see the same restrictions in other documents, e.g. 3rd party purchase order created from SO don't behave the same exact way as a "standalone" PO. Make sure not to break anything.
Also see Google -> 'how to find BADI site:sap.com'.