"Cannot allocate memory" when open /dev/camera in Qt

hi

I receive "Cannot allocate memory" error when try to open("/dev/camera",0);
in Qt on a mini2440 board equipped with
Qtopia2.2 + QtEmbedded4.6.3 + Linix2.6.32.2 + arm-linux-gcc-4.4.3(EABI)

system("chmod -R 777 /dev") , some times, randomly solve the problem (with
6 times try to opening!)
please be informed that open("/dev/pwm",0); in Qt, work fine.
and 'Qtopia System Info' shows that still there is free 44MB RAM + 13MB
flash !

while this {open("/dev/camera",0);} work fine, in a console application,
compiled with Makefile:
arm-linux-g++ camtest.cpp -Wall -O2 -o camtest
arm-linux-strip -s camtest

also, most of times, there is similar problem for the proposed console
application when it runs with QProccess  


how can it be solved?

thanks in advance

Has the qtopia friendlyarm application examples of mini2440
update(2010-8-18), compiled with QtE4.6.3 ?

Have I to downgrade to older versions to overcome the problem?