Bypass 16-point touch calibration

Does anybody have an idea how to bypass 16-point touch calibration appearing
on first calibration of a digitizer device. I am working with a capacitive
touchscreen and don't need the extra outside square and some users find it
hard to get their fingers on the corner spots. The 16-point calibration
shows up on first user calibration and then the 4-point calibration is used
from second time on. I would like to skip straight to the 4-point
calibration even if the touch digitizer has never been calibrated before.

Thanks for any help.