Default Disable build-in phone in qtek 1010

Hi all,
i'm developing an application that makes a data call over GSM network.
The data connection work fine beteween pda ipaq + gsm mobile via infrared and a qtek 1010.
My problem is that when a DATA call arrive to my qtek, a big "modal dialog" appear on the screen as happen when a normal voice call arrive...
This dialog is from the original phone program in pocket pc phone edition and cover all the screen so i cant answer the data call from my application...do u know how can i disable the phone program or replace it with my own application?

Thanks u
Fabio

P.s. i'm sorry my english is sooo bad!