I have ZCS 7.1.1 in split DNS config, installed on Ubuntu 10.04 LTS (x64) running in a test environment on VMware Workstation 7.1.
I had made the default installation (1 scsi disk) with default partitioning structure.
Tried adding a second scsi disk on vm so i can separate zcs installation (/opt/zimbra) from ubuntu system.

Linux ubuntu-server 2.6.32-28-server #55-Ubuntu SMP Mon Jan 10 23:57:16 UTC 2011 x86_64 GNU/Linux

Steps i've followed (all actions run by root user):

1. add new scsi disk on vm.
2. fdisk /dev/sdb1
3. mkfs -t ext4 /dev/sdb1
4. su zimbra -> zmcontrol stop
5. vi /etc/fstab and enter "/dev/sdb1 /opt ext4 defaults 0 2"
6. mv /opt/zimbra /home
7. reboot
8. run again the installation of ZCS 7.1.1 and selected clean installation.
9. reboot
10. su zimbra -> zmcontrol stop -> exit
11. mkdir /opt/zimbra
12. cp -Rp /home/zimbra /opt/zimbra
13. chown -R zimbra:zimbra /opt/zimbra
14. /opt/zimbra/libexec/zmfixperms
15. su zimbra -> zmcontrol start

zimbra@ubuntu-server:/home/acid$ zmcontrol -v
Release 7.1.1_GA_3196.UBUNTU10_64 UBUNTU10_64 FOSS edition.

zimbra@ubuntu-server:/home/acid$ zmcontrol status
Host ubuntu-server.localdomain
antispam Running
antivirus Running
ldap Running
logger Running
mailbox Running
mta Stopped
postfix is not running
snmp Running
spell Running
stats Running
zmconfigd Stopped
zmconfigd is not running.

[Bash] 2011-10-18 13:26:39,778 zmconfigd CRITICAL [10895-MainThread] zmconfigd started - Pastebin.com

I can access both webmainl (with all mails & accounts) and admin console.
When i try to send a new message i get an error that zimbra cannot communicate with MTA:

[C] A network service error has occurred. method: [unknown] msg: system failure: U - Pastebin.com

Any thoughts?

Thank you