I'll confirm that this this is still an issue, with certain versions. I built a load balancer template based on Ubuntu JeOS 8.04 and all clones of that template have required that fix.
From my own notes:
Change the Hostname -
A couple files need to be modified to reflect the desired hostname. Change the
“pentemplate” entries in the hostname and hosts files, then activate the change:
$ sudo su
nano /etc/hostname
nano /etc/hosts
/etc/init.d/hostname.sh start
exit
$ logout
Log back into the system and the hostname displayed should now be correct.
Fix the Network -
Modify the IP address of the system:
$ sudo nano /etc/network/interfaces
Delete the file causing network interface conflicts:
$ sudo rm /etc/udev/rules.d/70-persistent-net.rules
If you've installed MTA, it also needs to be fixed:
$ sudo dpkg-reconfigure exim4-config
Then reboot.