[DirectFB] Keyboard input repeats itself twice

I am using qt 4.7 branch from GIT. I built my app with -qt-gfx-directfb using DirectFB 1.4.0 and I set QWS_DISPLAY to directfb. Whenever I try to input some values using my usb keyboard each character repeats itself twice, so if I try to write nokia, it becomes:

nnookkiiaa

Same problem does not happen with the unaccelerated framebuffer interface.