Reconciling Bank Transfers across Ledgers

I have a client who implemented R12 using multiple Ledgers.  Each Ledger has it's own bank, but from accounting perspective they have different balancing segment and for transaction purposes, they are segregated entities.  However, the banking is more central.  Bank One Ledger One will transfer money to Bank 1 Ledger 2 to process other transactions.  How can this transaction be entered / matched while keeping accounting integrity?  Utilizing a bank transfer activity will always leave an open balance in the account of each entity.

Please advise....

Thanks