Hello Ben,

   BC> Since it is world readable and executable, I would start looking
     > in the file itself.  Are you certain the full path is /usr/local
     > /libexec/lpfilter?

#pwd
/usr/local/libexec

   BC> What is the first line of lpfilter?  I would assume it is the
     > hash-bang and the full path of the interpreter.

#cat lpfilter
#!/bin/sh
# Treat LF as CR+LF
printf "\033&k2G" && cat && exit 0
exit 2

   BC> Does the interpreter exist at that path?  Is it readable and
     > executable?

#ls -l /bin|grep sh
-r-xr-xr-x  1 root  wheel  139426 Oct 24 21:56 csh
-r-xr-xr-x  1 root  wheel  192197 Oct 24 21:56 ksh
-r-xr-xr-x  1 root  wheel  128039 Oct 24 21:56 sh

Thanks,
   - Andy Ball.