Weaknesses around control accounts

I'm doing a review around control accounts for the audit dept.

One of the items raised by them is controls review prior to the year end audit was weaknesses around control accounts (e.g. supplier and creditor liability accounts).  Currently Oracle in R12 has "flexfield security" and third party control accounts to prevent manual journal entries (to control accounts). 

There are however limitations with the current approach:

 

(i) subledger transactions are prevented from posting to control accounts unless “third parties” are defined and this creates a conflict with posting from sub ledgers – e.g. Fixed Assets, where the restriction has to be removed (manually) at month end in order for the sub ledger to post to the General Ledger;