Comment 8 for bug 245219

Teej, as M. Vefa pointed out, the problem is not in the distribution but on the Ubuntu HTTP servers.

The Content-Encoding header mentioned by Bob Drzyzgula in the original report seems to be gone now.

However, Content-Type is now application/x-gzip which is incorrect for a PGP signature. I haven't tested upgrading through a proxy recently, but it's still possible that this header could break that.

It looks like mod_mime matches extensions in the middle of a file name if the final extension is unknown. This explains why for files with a .tar.gz.gpg extension, the Ubuntu servers used to indicate a gzip encoding and a tar content type, and why they now return a gzip content type.

Here is what the Ubuntu servers currently reply:

$ wget -q --no-cache --save-headers http://archive.ubuntu.com/ubuntu/dists/hardy-proposed/main/dist-upgrader-all/0.87.31/hardy.tar.gz.gpg
$ cat hardy.tar.gz.gpg
HTTP/1.1 200 OK
Date: Sun, 17 Jan 2010 13:00:31 GMT
Server: Apache/2.2.8 (Ubuntu)
Last-Modified: Thu, 29 Jan 2009 15:38:41 GMT
ETag: "bd-461a0e1fda240"
Accept-Ranges: bytes
Content-Length: 189
Keep-Alive: timeout=15, max=100
Connection: Keep-Alive
Content-Type: application/x-gzip

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQBJgc2BQJdur0N9BbURAnhDAJwNh53DLg9jF8c3+dcjTKM+CnpK6gCggG9e
2Fi2CguhyGmEktTiVEQT4Hk=
=5Ug/
-----END PGP SIGNATURE-----

$ wget -q --no-cache --save-headers http://archive.ubuntu.com/ubuntu/dists/lucid/main/dist-upgrader-all/0.131.3/lucid.tar.gz.gpg
akaihola@morris:/tmp$ cat lucid.tar.gz.gpg
HTTP/1.1 200 OK
Date: Sun, 17 Jan 2010 13:04:35 GMT
Server: Apache/2.2.8 (Ubuntu)
Last-Modified: Tue, 12 Jan 2010 19:27:03 GMT
ETag: "bd-47cfca3780fc0"
Accept-Ranges: bytes
Content-Length: 189
Keep-Alive: timeout=15, max=100
Connection: Keep-Alive
Content-Type: application/x-gzip

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQBLTM0HQJdur0N9BbURAgoQAJ9jwi/0EBi+Hd5VWivJ90SYhRFwsQCggxR/
Y2Z4yunLdiqmR9x2DrOUxM4=
=tv7O
-----END PGP SIGNATURE-----