SDL on PocketPC

[ufff]

Sorry, I don't know where the appropriate place to ask this...

I am trying to use SDL on my PoocketPC (Gigabyte MW700 + Windows Mobile 6.1).

I downloaded the following files and built the libSDL.a.
(Actually, this is not matter to build the libSDL.a myself or get it from wince-gcc-libs.tar.bz2 - the problem's occurred anyway)

cegcc_mingw32ce_cygwin1.7_r1375.tar.bz2
http://www.libsdl.org/release/SDL-1.2.6.tar.gz
http://users.uoa.gr/~knakos/scummvm/lib ... 90809_diff
http://users.uoa.gr/~knakos/scummvm/lib ... bs.tar.bz2

Then I compiled testsprite.c from SDL test folder:
arm-mingw32ce-gcc testsprite.c -lSDL

Used screen parameters are:
width = 240;
height = 320;
video_bpp = 16;
videoflags = SDL_SWSURFACE|SDL_FULLSCREEN;

The testsprite works fine until something else tries to draw on the screen (e.g. incoming call or SMS). In this case SDL_Flip and SDL_UpdateRects crash the application.

What can be wrong?

Thanks!