Some of our CE based devices are switchable between VGA and QVGA, but not the Windows Embedded Handheld (aka Windows Mobile). I know that there have been custom OS builds in some cases generated to support QVGA for some VGA Windows Embedded Handheld devices, but it would be a custom product request through the Zebra custom products group.
Thank you very much for answering so fast!
So I guess I have to find out why our application is not scaling all parts as necessary... ;-)
Maybe something with enabling/ disabling hi_res_aware - as I found one of our application.exe which is quite old but scales perfectly.