How do I suppress the "New release '12.10' available" message?

When I ssh into my Mythbuntu box, I get this message:

Welcome to Ubuntu 12.04.1 LTS (GNU/Linux 3.2.0-32-generic x86_64)

 * Documentation:  https://help.ubuntu.com/

New release '12.10' available.
Run 'do-release-upgrade' to upgrade to it.

Last login: <redacted>
$

But I don't intend to upgrade to 12.10, because Mythbuntu recommends using LTS releases only.

How do I suppress the "New release '12.10' available" message? I don't want to be notified until the next LTS release is available.

I've already gone to Update Manager > Settings > Updates and selected "Notify me of a new Ubuntu version: For long-term support versions", but that didn't get rid of this message.

The other answers aren't quite right, but combining them put me on the right track.

/etc/update-manager/release-upgrades controls what updates you'll be notified about. /usr/lib/update-manager/release-upgrade-motd generates the "update available" message. The problem is that release-upgrade-motd caches the message, which means that once it's been generated, changing /etc/update-manager/release-upgrades doesn't get rid of the message.

So the answer is:

1. Tell Update Manager what releases you want to be notified about.

2. sudo rm /var/lib/update-notifier/release-upgrade-available to get rid of the cached message.

Note: For version 13.04 (and later), the path has changed. So point 2. to get rid of the cached message is now:

sudo rm /var/lib/ubuntu-release-upgrader/release-upgrade-available

That message is apart of the "Message Of The Day" (MOTD) system. If you just want to disable the update message:

Step 1:

Use a text editor to open "/etc/update-motd.d/91-release-upgrade"

sudo nano /etc/update-motd.d/91-release-upgrade

Step 2:

Comment out (put "#" in front of each line) all of the code within that file so that it looks like this

#!/bin/sh

#if [ -x /usr/lib/update-manager/release-upgrade-motd ]; then
#    exec /usr/lib/update-manager/release-upgrade-motd
#fi

Step 3:

Logout and log back in.

Step 4:

Done!

That should work for both Ubuntu Server 11.10 and 12.04 LTS

Try Editding /etc/update-manager/release-upgrades

Change Prompt from normal to lts or never;-)