Function PO_ORDERS_SUMMARY setup incorrectly, preventing the creation of custom menu for BWC

I´m trying to create a custom menu for the Buyer Work Center .I've created the menu and it works correctly, however when I take some actions like communicate a purchase order on the order summary page the system system takes me back to the standard menu instead of the custom menu.

I've diagnosed the issue and I can see that this happens because a standard function is setup incorrectly (see details below), has anyone else had this issue and found a way around it with out changing the standard function?  

The function: PO_ORDERS_SUMMARY like for example PO_AGREEMENTS_SUMMARY are used as a hard coded reference in many places in the system where the system has to redirect the user to a page. Example of this is when a user in the buyer work center prints a purchase order using the "communicate" functionality. Then the system uses this function to redirect the user back to the PO Orders Summary Page.