Printer User Interface Driver Question

Hi All,
Right Now i am developing Printer User Interface Driver which is a filter
driver to my base driver(like unidrv.dll).
In our User Interface i have my own tab(extra property sheet).
I have base driver UI which enumerates and displays all the paper sizes
that the system supports.
But some of the paper size is not supported by my printer.
I want to hide the unsupported paper sizes in my base driver when
selecting the papaer size before printing.and i dont have the source code
for my base driver.

Thanks in Advance.