[Hardy] do-release-upgrade doesn't retrieve hardy gpg key

I have the same problem. Trying this behind a proxy.
As you can see in the wireshark output, only one request is made and no request is made for the .gpg file.
wireshark output:

GET http://changelogs.ubuntu.com/meta-release HTTP/1.1
Accept-Encoding: identity
Cache-Control: No-Cache
Connection: close
User-Agent: Python-urllib/2.5
Host: changelogs.ubuntu.com
Proxy-Authorization: Basic basicauthisdumb
Pragma: no-cache
If-Modified-Since: Tue Apr 29 19:01:56 2008

HTTP/1.1 304 Not Modified
Date: Tue, 29 Apr 2008 19:52:27 GMT
Server: Apache/2.0.55 (Ubuntu) mod_python/3.1.4 Python/2.4.3
Last-Modified: Thu, 24 Apr 2008 12:25:57 GMT
ETag: "29401e-cbb-8d27ff40"
Accept-Ranges: bytes
Cache-Control: max-age=7200
Expires: Tue, 29 Apr 2008 21:52:27 GMT
Content-Type: text/plain; charset=UTF-8
Connection: close
Age: 0

@peitschie: do-release-upgrade is not designed to work for hardy->hardy upgrades (like from beta->rc). That is the job of the normal update-manager or for apt-get dist-ugprade. I'm susprised that it downloaded anything at all for you, what is the output of lsb_release -a on this system?

@Ashwin: It looks like your problem is slightly different. You probably get a message like "no new release found" (or similar). Could you please try to remove /var/lib/update-manager/meta-release and run "sudo do-release-upgrade" again?

@michael: That would explain things. It downloaded quite a few packages and seemed to work ok. I have been running the computer and it isn't asking for a distro update. All packages appear to be updating correctly as well. So I have suffered no ill effects so far.

Doing an lsb_release -a gives:
No LSB modules are available
Distributor ID: Ubuntu
Description: Ubuntu 8.04
Release: 8.04
Codename: hardy

Sorry, I finished the upgrade by taking the laptop home :)
I filed another bug for apt problems behind proxy (I used to get the gunzipped .tar.gz file). It is reported here:

https://bugs.launchpad.net/ubuntu/+source/apt/+bug/230832

I suspect this issue will be fixed by that fix as well.

We are closing this bug report because it lacks the information we need to investigate the problem, as described in the previous comments. Please reopen it if you can give us the missing information, and don't hesitate to submit bug reports in the future. To reopen the bug report you can click on the current status, under the Status column, and change the Status back to "New". Thanks again!

This was an issue for me, too. If you're using a proxy, like apt-cacher-ng, you can't download the gpg files and the upgrade fails early. See this thread:
http://ubuntuforums.org/showthread.php?t=436018

Easy to reproduce.