gui in half screen

hi,
I have developed my application on debian and uses directfb for gui, i uese the kernel 2.6.11.8
when i prepare the live cd using knoppix i am only able to see the half screen of my applications gui.
the gui comes only on the half screen cutting the other half part.
how can i be able to see the whole gui.
pls help its urgent.
I have developed my application on debian and uses directfb for gui, i uese the kernel 2.6.11.8
when i prepare the live cd using knoppix i am only able to see the half screen of my applications gui.
the gui comes only on the half screen cutting the other half part.
how can i be able to see the whole gui.
pls help its urgent.