lammert - 7:05 am on Dec 14, 2012 (gmt 0)

I have sieved through the log files of a similar bug report in the Ubuntu bug tracker and there are many errors related to files which cannot be opened. Could you therefore login as user root and try to print from that account? You should do a full login as this user, not just going to root user level with the su or sudo command to be sure that all login scripts are properly parsed and all needed environment variables are set.