Touch screen "sticky buttons" problem (Linux, QT4.5.1, Penmount 9000 driver)

Hello,
I met a problem with touch screen events in my application. OS: Linux, Driver: Penmount PM9000).
With my app compiled with qt 4.5.1 (Debian squeeze) I get sticky buttons i.e. after I release a button it may stay highlighted (pressed state). Similar problem I got with QT calculator example. It doesn't impact functionality, just confuses user but is a quite serious problem. This doesn't seem to be a driver problem as GTK applications work fine.
The problem is not reproduced under Windows with the same version of QT.
The problem is not reproduced if I re-compile the application with QT 4.6.
Did anyone meet such problem?
Thank you.