Same story here: MF4150 worked in 11.04 but not in 11.10. I am running 64-bit version.

I installed these two drivers (converted them from rpm that are provided on Canon website) without problem as I did in 11.04

sudo dpkg -i cndrvcups-common_2.20-2_amd64.deb
sudo dpkg -i cndrvcups-ufr2-us_2.20-2_amd64.deb

however when I print I get an error:

printer-state-message="/usr/lib/cups/filter/pstoufr2cpca failed"

I do not have the files mentioned in the previous post (I did locate), I do not even have /user/lib64 folder, only /user/lib and /user/lib32.

Could someone help me with this please?