Bug#381491: apt-get doesn't like gpg signatures with proxy

[Charles Samuels <charles@kde.org>]

Package: apt
Version: 0.6.45

When I use a proxy with apt-get, it says this for all packages:

>>>>
WARNING: The following packages cannot be authenticated!
...
Install these packages without verification
<<<<

It doesn't say anything else relevant to GPG (like that the keys didn't match 
or something)

So here's what I did to cause this:

1) Activated my proxy:
Acquire::http::Proxy "http://altair.derkarl.org/";;
(which does caching for me via apache2's proxy and cache modules)

2) apt-get update:
Ign http://linux.csua.berkeley.edu unstable Release.gpg
Ign http://www.debian-multimedia.org sid Release.gpg
Ign http://linux.csua.berkeley.edu unstable Release
Ign http://www.debian-multimedia.org sid Release
Ign http://linux.csua.berkeley.edu unstable/main Packages/DiffIndex
Ign http://linux.csua.berkeley.edu unstable/contrib Packages/DiffIndex
Ign http://linux.csua.berkeley.edu unstable/non-free Packages/DiffIndex
Ign http://www.debian-multimedia.org sid/main Packages/DiffIndex
Hit http://www.debian-multimedia.org sid/main Packages
Hit http://linux.csua.berkeley.edu unstable/main Packages
Hit http://linux.csua.berkeley.edu unstable/contrib Packages
Hit http://linux.csua.berkeley.edu unstable/non-free Packages

(note how it's "Ign"oring the Release.gpg files)

3) do an apt-get upgrade:
Reading package lists... Done
Building dependency tree... Done
The following packages have been kept back:
  cupsys kaddressbook ntp nvidia-glx nvidia-kernel-source twinkle
The following packages will be upgraded:
  ....
110 upgraded, 0 newly installed, 0 to remove and 6 not upgraded.
Need to get 114MB of archives.
After unpacking 1453kB disk space will be freed.
Do you want to continue [Y/n]?
WARNING: The following packages cannot be authenticated!
  ....
Install these packages without verification [y/N]?


If I disable the proxy, do an apt-get update,then enable the proxy and do an 
upgrade (without an additional upgrade), then it works just fine.

I can reproduce this on two machines, one being a brand new install.

If I do an strace on apt while upgrading (as it has no other methods of 
diagnosing bugs), it suggests that it cannot open the Release.gpg file 
(Because it's not there, and it isn't)

charles