Foreign Currency Valuation - Resetting Posting on Basis of Valuation History
After postings have been made, you can reset them at a later point in time. For this, the program determines the relevant foreign currency items (line items) and foreign currency balances (accounts) as well as any corresponding valuation differences from the entries in the valuation history. In the case of foreign currency items, the system also creates a reset posting if the items were cleared before or on the specified valuation key date. It is not possible prior to enhancement pack 5 to reset posting, if the items were cleared before or on the specified valuation key date. This new functionality is only available via Enhancement pack 5.
http://wiki.sdn.sap.com/wiki/display/ERPFI/Foreign+Currency+Valuation++-+Resetting+Posting+on+Basis+of+Valuation+History
