Modifying transacations using subledger accounting

 We are currently in the process of upgrading to R12.  As part of the upgrade, we want to be able to change some of our accounting entries.  For example, we have transaction types set up in Order Management where the COGS account gets overrriden by our workflow.  For this particular transaction type, I want to use all of the segments listed in the COGS field.  Instead, it goes back to our auto accounting rules (we have modified the COGS workflow).  I have been told by Oracle that this can be accomplished using subledger account.  At a quick glance, nothing sticks