On the page http://welcome.solutions.brother.com/bsc/public_s/id/linux/en/instruction_scn1c.html#u9.10 , Brother instructs users to open /lib/udev/rules.d/40-libsane.rules and add
# Brother scanners
ATTRS{idVendor}=="04f9", ENV{libsane_matched}="yes"
Strangely, they didn't contact you to tell you this...
Best regards,
Leif Arne Storset
