Using a freshly installed version of Ubuntu 9.10, I was unable to successfully install zoneminder using the apt-get install zoneminder command. Instead I was getting messages such as:

Unknown database 'zm' at /usr/share/perl5/ZoneMinder/Config.pm

To resolve I did the following (although I am not certain all the following steps were necessary):

1. Purged apache2, mysql-client, mysql-server, mysql-core, and zoneminder. I did this using the Synaptic package manager but it just as easily be done using apt-get purge
2. I executed sudo apt-get --purge autoremove to clean all the additional packages
3. I installed libdirac0c2a and libdirac-dev
4. I installed mysql using sudo apt-get install mysql-client mysql-server
5. I installed apache using sudo apt-get install apache2
6. I removed the startup warning apache2: Could not reliably determine the server’s fully qualified domain name, using 127.0.1.1 for ServerName by adding ServerName to the apache2.conf file in /etc/apache2.
7. Executed sudo apt-get install apache2-mpm-prefork to ensure it successfully restarted apache
8. Installed nullmailer using sudo apt-get install nullmailer and went through the configuration, setting my smarthost appropriately
9. Installed the additional dependencies for zoneminder to ensure they all were successful using sudo apt-get install ...
10. Finally, I installed zoneminder successfully using sudo apt-get install zoneminder

I believe the tricks were to install the nullmailer separately and also purge the existing apache, mysql, and zoneminder installations prior to the install.

My Exchange server is behind a Linux firewall with sendmail fronting the email handling. I started seeing messages in the maillog on the Linux machine like:
dsn=4.0.0, stat=Deferred: Connection reset by mailserver.

Following that were even odder messages from SpamAssassin:
mailhost mimedefang-multiplexor[1614]: Slave 0 stderr: dns: sendto() failed: Connection refused at /usr/lib/perl5/vendor_perl/5.10.0/Mail/SpamAssassin/DnsResolver.pm line 411.
mailhost mimedefang-multiplexor[1614]: Slave 0 stderr: Use of uninitialized value in string ne at /usr/lib/perl5/vendor_perl/5.10.0/Mail/SpamAssassin/AsyncLoop.pm line 174.
mailhost mimedefang-multiplexor[1614]: Slave 0 stderr: plugin: eval failed: oops, no key at /usr/lib/perl5/vendor_perl/5.10.0/Mail/SpamAssassin/AsyncLoop.pm line 174.

This was all due to the added security of the Exchange Server installation (I believe it is also true for 2007). It is set up for authenticated connections and to disallow anonymous connections.

To resolve, I added a new Receive Connector in the Exchange Management Console for my sendmail front end machine under Hub Transport in the Server Configuration. I set this up to only receive mail from the IP Address for my sendmail machine and checked the Anonymous users permission group. Adding this new Receive Connector allowed email to be received from my sendmail machine once again.

In simpler terms:

1. Open Exchange Management Console
2. Click on Hub Transport under Server Configuration
3. Click on the corresponding hub in the top section
4. Right-click on the bottom section and add New Receive Connector
5. Using Custom as the intended use:
1. Listen on Port 25
2. Enter the desired FQDN
3. Edit the IP Range to match the address of the sendmail machine
4. Create the New Reveice Connector
6. After the Receive Connector is created, right-click on it and select Properties
7. On the Permission Groups Properties tab, select Anonymous users and press OK

A working system!

Rebooted the server last night and the screen would not get past Applying computer settings… There seemed to be very light disk activity. I discovered that if I rebooted in Safe Mode with Networking and re-enabled the IPv6 on my Local Area Connection, the system would boot normally. I had turned it off earlier but had not rebooted since that change.

Steps:

1. Right click on my network connection in the system tray and select Open Network and Sharing Center
2. Display the Local Area Connection Status
3. Click Properties and make sure Internet Protocol Version 6 (TCP/IPv6) is checked
4. Quit everything and reboot

The only other potential factor was the server was behind a NAT; it could communicate with the local network but could not reach the outside world due to a misconfiguration in the firewall.