Interunit Asset Transfers

We have the requirement to have all interunit transfers pass through our corporate business unit. So, no business unit should create interunit transactions with another business unit without going through the corporate business unit. Short of customizing the interunit processor, does anyone have any suggestions for how to handle this situation?

Example:

BUS1 needs to transfer asset to BUS2.

Accounting needs to be:

BUS1      1xxxx                                  -100

BUS1     I/U       CORP (affiliate)         100

CORP    I/U       BUS1                        -100

CORP    I/U       BUS2                         100

BUS2     I/U       CORP                       -100

BUS2     1xxxx                                    100