For a unique goods issue scenario, we are trying to derive the WBS element based on valuation class in a goods issue posting through the MB1A transaction. In the test mode of FMDERIVE and activating the 'trace' feature in FMDERIVE, the WBS element is being derived and populated in the WBS element field. However, when the goods issue is posted and the accounting document is viewed, the WBS element field is EMPTY. We have tried really hard to figure out what is going on, but to no avail.
In one of the other postings, I found reference to a function module (PSPNUM_EXTERN_TO_INTERN_CONV) that changes the wbs element from an external number to an internal number - I do not know how this works or what exactly this does. Furthermore, i dont see this function module in our list in fmderive. What we do have is FMDT_CONVERSION_WBS_INT_TO_EXT - can i use this instead? What does this do?
If i were to use this function module what would the source and target fields be?
Can one of you please help?
Are there any other ways to accomplish this? or is it a standard functionality that WBS element is not derived in a goods issue posting?
Please let me know.