[ALUG] Preventing ouput mail from shell script

Hullo there, I'm trying to prevent a very simple script in cron.hourly from sending mail when it executes. The script consists of mount -a > /dev/null I hoped the output would be directed to a black hole, but it sends a mail every hour as below. /etc/cron.hourly/checkmounts: mount: knossos:/home already mounted or /nfshome busy mount: xios:/home already mounted or /nfshome-xios busy run-parts: /etc/cron.hourly/checkmounts exited with return code 32 Is the only way to prevent mail output to make the script more complicated with exit codes and whatnot? Thanks, Jenny