Cash in Bank Accounts module?

Hi, I am an employee of a company that begins to implement Navision Financials. Our accountant manager wants to use something like cash desk module (cash) for the control of effects (present money). But we just have the standard application only (without any external modules) and there is no such a utility. Therefore I would like to ask you a question: is it possible to use a Bank Accounts in General Ledger for this purpose and to control this element in the same way as bank accounts (I obviously know I have to fill in an appropriate Bank Account Posting Group in the TabControl)? Is it a “good” idea or a madness? Thank you very much. Krumpin