Hi again, and thanks for your quick answer. The screen resolution is 320x240.
I cannot remember the exact error mesage, but I was probably using a wrong version : following the advice of a co-owner,
i've tried the scummvm-0.6.1b-HandheldPC_ARM.zip build, which is working.
As the device has sold massively since it debut in november, as ScummVM is a very nice software which its users will be happy to use, and as I am eager to follow on with newer versions, you may wish to update this port from time to time. Keep up the awesome work