This article really helped me a lot, many thanks to Andrew Smith and Brian.

I only want to give some additional information.

I have a Brother all-in-one as well, a DCP-135C and your how-to worked very well on this, too.

I'm using Slackware 12.2 and the standard installation already included perl 5.10 which worked well.

IMPORTANT: Some really nice guy, Bruce S. Babcock, made an alien-extra package that includes all extra files and stuff you need for the Slackware instalation! This information was in the readme.
I created a folder and extracted both the alien installation files and the alien-extra files into it. Then i run the order as given in the install file. And alien worked.
NOTE: There are two packages you have to download from http://solutions.brother.com/linux/en_us/download_scn.html
brscan2 and the scankey
I converted them both, installed them as shown and the scanner worked!

If you don't want to download and install alien, just ask me about the converted rpms.