ok, so I don't understand why this is not working.... I'm sure it's just something simple and stupid that I'm doing wrong. If I run this script manually, it works great, but when I set it up as a cron job, it seems to run (it logs it in the log file I made and makes the bz2 file) but the bz2 file ends up being blank.

I'm doing two rsync's, so that I can copy everything I can while zimbra is running and shut it down as short a time as possible for an additional rsync.

I'm running Zimbra 6.06 opensource edition on Ubuntu Server 8.04 LTS.

the cron job I setup was as follows:

00 01 * * * /etc/customscripts/zimbrabackup

The script is this:
DAYOFWEEK="`date '+%A'`"

date >> /diskbackups/zm-backup.log 
echo "Backup Started."  >> /diskbackups/zm-backup.log 

mkdir /diskbackups/TEMP
rsync -ruavzHp /opt/zimbra/ /diskbackups/TEMP

/etc/init.d/zimbra stop
pkill -9 -u zimbra
rsync -ruavzHp /opt/zimbra/ /diskbackups/TEMP
/etc/init.d/zimbra start

tar cjpf /diskbackups/"backup_zimbra.${DAYOFWEEK}.tar.bz2" /diskbackups/TEMP/
rm -rf /diskbackups/TEMP

#Keep track of Ending date and time
date >> /diskbackups/zm-backup.log
echo "Backup Completed." >> /diskbackups/zm-backup.log