Just a quick note: after a day of emailing with an understanding Brother support, it appears that if you want to get the HL-L8250CDN working under Arch Linux, and you're out of luck extracting the
.deb and or the
.rpm packages, you can use the - still proprietary, but working drivers for the HL-L8350CDW.
Under Arch Linux, that means an easy
yaourt -S HL-L8350CDW.
Afterwards, you just visit the cups web configuration utility and add the printer there. Hint: use the AppSocket/HP JetDirect socket.
Brother Belgium cannot GPL their drivers, as Japan is the HQ in charge. "It's a bit like NVidia and AMD".
If you have a similar printer, want to get into reverse engineering and you're in a legislation that allows that (basically European Union, or you want to take the risk), get in touch with me. My contact details are on my consulting page.