Comment 29 for bug 68267

A couple of things in the x11-common.config
script validate_nice_value() don't look right to me:

 1) That "set +e ... set -e" seems -really- bogus.
      That forces exit on non-zero exit status from
      simple commands, and this script intentionally
      invokes some simple commands that might exit
      non-zero, such as the expr line on the very next
      line after the "set +e".

 2) I believe that expr can exit with 3 if asked to
     subtract non-numbers. So I'd suggest changing
     the line:
         if [ $? -ne 2 ]; then
     to be instead the line:
         if [ $? -lt 2 ]; then