Exit/BTE for tx F110 (SAPF110S), Automatic Payments (field XREF3)

Question

Hello,
I have been searching for a long time the posts in the forums regarding similar issues, but I can not find a suitable solution.
The problem is:
It's needed to fill one field of the payment document (BSEG-XREF3) created by tx F110, with the value coming from the original  document (REGUP-XREF3) that is processed by F110 (SAPF110S).
I can not find a BTE / exit that: 1) Could be reached during F110 execution and 2) contains data from both documents, or something similar that could allow me to gather the data from both documents.
Let me say that I'm very AWARE of the fact that SAPF110S schedules and executes all this processes in background; I am debugging it using the okcode JDBG in tx SM37. In fact, I can "reach" and debugg another BTE already in use (BTE process 1120, FI document creation), when the payment document is created. This one could be suitable to pass the value to the payment document that is to be created.
The other BTE only reached is BTE process 1830, but this one is only executed during proposal creation, and although I get access to REGUP values, the only possibility is to save the value with SET/GET parameters statement, in order to pass the value in memory for the next execution of F110, but this approach is not good at all.
Any ideas? Somebody has resolved something similar?
(In forums, a lot of people talks abouts exits or BTEs that they has never used before).
I have tested various of the user-exits that came across searching in the forums, and the BADI FI_F110_SCHEDULE_JOB, but:
-No one of the u-exits works, and
-The BADI is not suitable for solving the problem.
Thanks in advance,
José Gabriel Martínez.
Edited by: José Gabriel on Sep 7, 2009 2:06 PM

Answer 1

Hi Manohar,
I haven't tried substitutions-GGB1, I just used it one time, a long time ago, just to validate and substitute one value according to a Z table field.
But, I am not sure, may be because I am not used to use this tool, but I can not figure out how to "get" the data of both documents at the same time and perform the changes, using this tool.
For example, if you check the BTE - "Interface" 1025, this one could be an excellent solution, because I tested it, it is triggered, and it gives access to the needed data and structures to accoplish the requested task.
But, it isn't suitable, due to the fact that this BTE-interface-1025 is P&S, so, it is not intended for perform changes to the FI documents. That is way I am looking for a BTE-Process, like the one associated to event 1120.
Even, BTE-"Process"-1640, looks like the right one according to its documentation, but unfortunately it isn't triggered, I don't know why (like all of my tests, I copied the FM, and entered the corresponding entry, with active product, using tx FIBF).
Have you used substitutions-GGB1 to solve the same problem with F110-Payment Program? Please, let me know how, if it is the case.
Regards.