Can't install GUI on server from Desktop CD

I have the need for a Ubuntu server with normal server components such as SSH, NFS, and Samba servers, system accounting and status, etc, but also need X components for the in-house application. I figured it would be easier to install the server version then add the desktop rather than install the desktop then add all the missing server bits.

The server is on a secure network with no Internet access.
With the desktop CD in the drive, I have modified /etc/apt/sources.list (both manually and with "sudo apt-cdrom add") so that I have the line:
deb cdrom:[Ubuntu 10.10 _Maverick Meerkat_ - Release amd64 (20101007)]/ maverick main restricted
and left the "...Ubuntu-Server 10.10 ..." line commented out.
then done:
sudo apt-get update
-> all good, with the usual Internet errors, BUT
sudo apt-get install ubuntu-desktop
fails with "Unable to locate package"
and aptitude only lists 33 new packages from the CD.
Tried clearing the package list ("forget new packages") and reloading -> still only 33.

Obviously dpkg/apt is somehow detecting that I have the server installed and is denying access to the non-server packages.

Is there a way to trick or force the installer, or to un-bundle the ubuntu-desktop package from the CD?

Workaround for GUI on server

Problem: need GUI on Server, no Internet access for getting packages, Server version can't see all of the packages on the Desktop CD.
One (ugly) way to work around this problem is to install the Desktop version, then add all the missing Server bits.
Unfortunately the Desktop version is missing large amounts of text-based stuff, including aptitude and the SSH server; but it does have apt-get. Either install aptitude and ssh bundle individually, or run Synaptic on the GUI - requires running the GUI through the ILO virtual console (not at all a pleasant experience) or put a head on the server (which you probably had to install the Desktop).
Once you've got a terminal and aptitude, and you've configured your network, you can have a slightly more pleasant time of installing all the missing server stuff. You can also start removing some of the useless desktop stuff.

Interestingly, the Desktop version can see all of the packages on the Server CD, but the Server version can only see 33 packages on the Desktop CD, hence this ugly workaround.

Adding a GUI to Server Edition Ubuntu (VERY EASY)

After logging in to you normal user account type at the command line prompt this:

sudo apt-get update [ENTER]
sudo apt-get -Y install xorg ubuntu-desktop [ENTER}

(The -Y answers yes to all promps. You can leave this out if you wish but you will have to manually answer prompts)

If you do not want to use the ubuntu desktop, you can also do the following and choose from a list of software:

sudo apt-get update [ENTER]
sudo tasksel [ENTER]

A blue interface will start and you can choose a different desktop from here.

After installing the desktop and quiting tasksel by pressing [Q], reboot your machine. It should boot up to the desktop that you installed.

After logging in to the desktop, look at the top of the screen where it says "Applications" and click on that. When the menu drops down you will see as your last option an application for installing and uninstalling software. It is fully searchable. You can search for applications to ease the configuration of your server there.

IMPORTANT Note: A GUI server is less secure than a console server because of the changes and additional software and services that it adds.

Adding a GUI ....(VERY EASY) -> If You Have The INTERNET

Sure, adding the GUI to the Server edition is easy if you have a connection from your server to the Internet.
Perhaps you missed the words:

"The server is on a secure network with no Internet access."

so I can't get the packages direct from the normal repositories;

"Server version can't see all of the packages on the Desktop CD."

so I can't get the packages from the Desktop CD (even though they are all there).

Hence my question: "Is there a way to trick or force the installer, or to un-bundle the ubuntu-desktop package from the CD?", and my follow up ugly workaround.

Until the installer is fixed so that it can see other CD repositories properly, the only other workaround I can think of is to install the Server version, work out all the packages I need for the GUI (including dependencies), download them individually to a USB stick, then install them one by one. Is that easier than retrofitting server functionality to the Desktop version using bundles from the Server CD, I ask myself..... probably not.