consume forecast from production plant

Hi gurus,

can i request you guys to help me out in this scenario.

Scenario:

1) we have plant A (a dsitributiuon center so to say, no production activity happens at this plant) and we have plant B where the actual manufacturing happens. There will be Planned independent requirements loaded into MD61 of plant B. we will not load any forecast in Plant A. Both Plant A and Plant B will get sales orders from the customers.

we will bring hte material from Plant B to Plant A using a STO.

now the question is what settings do i need to do such that the sales orders received in Plant A reduces the forecast in Plant B for a given material. Is this posssible at all?

I have tried in the system and i cannot reduce the forecast from Plant B when the sales order is created in Plant A. Are there any settings that i'm missing.

thanks

ravi