Sales Invoices, Credits, Purchase Invoices, Purchases Credit Notes - do not allow postings to Control A/Cs specified in Nominal Default Accounts

Users are able to post Sales Invoices, Credits, Purchase Invoices, Purchases Credit Notesto Control A/Cs- this can ends up making Control A/Cs go out of balance eg Debtors Control eg you in the nominal analysis you enter the debtors control - you then end with DR Debtors Control and CR Debtors Control .....