Did someone notice, that the Canon firmware logs errors to the rom?
I noticed some routines in the firmware, which seem to do that. So i dumped the whole last 4MB including the part which is usually not included in firmware dumps and noticed that ther seems to be a part at the end which contains an error log...
at least i think that part is rom as well (have not tried write and re-read yet), but the error code in with ver.req was still there after removing all batteries including backup battery. Btw. the total shot counter was also still there (hope they don't write that counter always to the same flash cell...).