I use a Debian Lenny distribiution of GNU/Linux. My scanner Plustek OpticSlim 2400+ was not mentioned in the '/etc/udev/libsane.rules' file.
After I have inserted the line: # Plustek OpticSlim 2400+ SYSFS{idVendor}=="07b3", SYSFS{idProduct}=="0454", MODE="664", GROUP="scanner" ,my scanner works. :-) Of course, first, after copying the firmware, I had to add to '/etc/sane.d/gt68xx.conf' these lines: usb 0x07b3 0x0454 vendor "Plustek" model "OpticSlim 2400+" firmware "/usr/share/sane/gt68xx/cis3R5B1.fw" override "plustek-opticslim-2400" Sincerely, Jaros?aw Arlet