there is an issue we have not yet identified. If we run the (old) x11zaurus X-Server on an SL5500 machine with 320x240 screen and ztsd which translates the zaurus touchpen device events to the iPAQ format required by X11fb it works fine.
Using the same X server on a C860 also works - but
* it can directly access the touchpen of the C860 which generates the proper format
* but it is not oriented properly
* if switched to 320x240 size and telling Qtopia to start the application in compatibility mode makes the touchpen jitter