A short digest, how to get Samsung SCX 4200 scanner working on Ubuntu 9.10; all needed packages (e.g. udev, libsane) are installed by default:
to "/etc/sane.d/xerox_mfp.conf" add: #Samsung SCX4200 usb 0x04e8 0x341b and to "/lib/udev/rules.d/40-libsane.rules" add: # Samsung SCX4200 ATTRS{idVendor}=="04e8", ATTRS{idProduct}=="341b", ENV{libsane_matched}="yes" it worked for me; max