Rick - can you verify that your machine hostname is listed in your /etc/hosts file? It should appear similar to this:
127.0.0.1 localhost macbook 127.0.1.1 macbook
If your machine only shows localhost on the first line try appending your hostname. This has been shown to make a difference.
Also, are you running the 64bit kernel? 32bit? What Ubuntu release and kernel version are you running please?
Rick - can you verify that your machine hostname is listed in your /etc/hosts file? It should appear similar to this:
127.0.0.1 localhost macbook
127.0.1.1 macbook
If your machine only shows localhost on the first line try appending your hostname. This has been shown to make a difference.
Also, are you running the 64bit kernel? 32bit? What Ubuntu release and kernel version are you running please?