Welcome to the forums,
Could you upgrade to
4.5.10?
Make a good backup of it first:
-run a zmbackup full and you can also grab the entire /opt/zimbra
-obviously backup any other mounted locations that you use, the below is just assuming everything's stored in /opt/zimbra/
su zimbra
zmcontrol stop
exit/switch back to root
ps aux | grep zimbra (kill -9 pid on any remaining)
mkdir /backup
rsync -avHK /opt/zimbra/ /backup/zimbra
When that finishes, if you want you can tar it up as well for 'easy' movement to another location:
mkdir /backuptar
tar -zcvf /backuptar/zimbra.457NE.200711##.backup.gz -C /backup/zimbra .