I need single sign on for both oscommerce and phpbb. When a user creates an account with oscommerce or phpbb, that account will be used by other script. When a user signon to one script (eg. oscommerce) and he wants to use also other script's membership required functionalities, there will not be a need for second signon process (eg. he can post messages to phpbb without login second time).
Note: I modified oscommerce and i dont use its shopping chart functionality. Both scripts will be in Turkish. Proposed modifications/additions will be opensource. All unit tests and integrations tests will be done by developer/bidder. After that, if system runs well, i will accept the code/modifications. If there are some outofbox solutions, also well come.