Comment # 2 on bug 1096755 from Johannes Meixner

I cannot test it myself because I do not have
a HP device with a scanner unit.

Markus Leuthold,
does it work for you when you manually modify your 
/usr/share/hplip/scan.py
according to the above diff?

I am not a python expert but perhaps you may have
to remove the associated pre-compiled files
/usr/share/hplip/scan.pyc
/usr/share/hplip/scan.pyo
(the two should be hardlinked)
to ensure your modified /usr/share/hplip/scan.py
gets actually used - or this might also happen
automatically by python?