Delving a bit further I found another way to start condor by using cron.
Create a script to start condor: sudo vim /usr/sbin/start_condor
Enter these contents, and customise to your installation:
# Ensure network is all setup
# Ensure condor environment is loaded
# Start condor
Our condor installation is actually stored on an NFS drive, so the 100 second sleep is to ensure the NFS drives have mounted before the rest of this script runs. I handle the path settings for
$CONDOR_CONFIG, $PATH & $MANPATH in a separate script (condor.sh), alternatively you could specifiy $CONDOR_CONFIG in this script.
Tell cron about your script, and that it should be run on boot:
sudo echo "@reboot root /usr/sbin/start_condor" >> /etc/crontab
I have the condor daemons run as root, hence the root user mentioned in this crontab entry.
Test the script by running direct from the command-line first, if it runs then you should have trouble when rebooting.