udev error

I noticed the security updates werent installing when apt-get update && upgrade, so I uncommented this line in the apt source file:
## Major bug fix updates produced after the final release of the
## distribution.
deb http://ch.archive.ubuntu.com/ubuntu/ precise-updates main restricted
deb-src http://ch.archive.ubuntu.com/ubuntu/ precise-updates main restricted

Then apt-get update and upgrade and then it was stuck with the udev issue...