[AccessD] Comma Decimal separator in UPDATE query

Hi,
I have a comma decimal separator and it isn't work in Update query. I want to open the Products form from "Order Details"(subform), modify the price, and get that new price on the subform. How can I force the Update query to accept it?
My query looks like:
DoCmd.RunSQL "Update tblOrderDetail set price=" & NewPrice & " where OrderNo=" & Order & " and ProductNo=" & Product
Many thanks in advance
    Ervin