Please describe the problem:
Rhythmbox fails to download podcasts from servers that don't implement HTTP HEAD queries.  When trying to start the download, Rhythmbox quickly reports a status of Failed and does not try to download the file.  When --debug is enabled, the following messages are printed:

(17:11:54) [0x815b218] [rb_podcast_source_cmd_download_post] rb-podcast-source.c:1296: Add to download action
(17:11:54) [0x815b218] [rb_podcast_manager_download_entry] rb-podcast-manager.c:420: Try insert entry for download.
(17:11:54) [0x815b218] [rb_podcast_manager_next_file] rb-podcast-manager.c:540: try lock file_process mutex
(17:11:54) [0x815b218] [rb_podcast_manager_copy_post] rb-podcast-manager.c:576: processing http://www.sciam.com/podcast/podcast.mp3?e_id=EB7A34D3-E7F2-99DF-3C75590478B496A8&ref=p_rss
(17:11:54) [0x815b218] [rb_podcast_manager_copy_post] rb-podcast-manager.c:588: hiding query string e_id=EB7A34D3-E7F2-99DF-3C75590478B496A8&ref=p_rss from gnome-vfs
(17:11:54) [0x815b218] [rb_podcast_manager_download_file_info_cb] rb-podcast-manager.c:637: got file info results for http://www.sciam.com/podcast/podcast.mp3?e_id=EB7A34D3-E7F2-99DF-3C75590478B496A8&ref=p_rss
(17:11:54) [0x815b218] [rb_podcast_manager_download_file_info_cb] rb-podcast-manager.c:655: get_file_info request failed
(17:11:54) [0x815b218] [rb_podcast_manager_next_file] rb-podcast-manager.c:540: try lock file_process mutex

The gnome_vfs_async_get_file_info function is probably implemented in terms of an HTTP HEAD request, which fails for some servers.  Case in point:

paul@kryten:~$ gnomevfs-info 'http://www.sciam.com/podcast/podcast.mp3?e_id=EB7A34D3-E7F2-99DF-3C75590478B496A8&ref=p_rss'
Error: Unsupported operation

paul@kryten:~$ HEAD 'http://www.sciam.com/podcast/podcast.mp3?e_id=EB7A34D3-E7F2-99DF-3C75590478B496A8&ref=p_rss'
405 Method Not Allowed
Connection: close
Date: Thu, 01 Mar 2007 22:34:35 GMT
Server: Netscape-Enterprise/6.0
Allow: GET, POST
Content-Length: 124
Content-Type: text/html
Client-Date: Thu, 01 Mar 2007 22:37:58 GMT
Client-Peer: 216.68.232.11:80
Client-Response-Num: 1
X-Cache: MISS from aries.sciam.com

Steps to reproduce:
1. Add the podcast feed http://www.sciam.com/podcast/sciam_podcast_r_d.xml to Rhythmbox.
2. Go to the podcast, right-click on one of the files, and select "Download Episode".


Actual results:
The error icon appears in the episode's line, and the progress bar for the episode says "Failed".

Expected results:
The podcast episode should download.

Does this happen every time?
Yes.

Other information:
This bug is *not* the same as #378155.  In that bug, the podcast episode does actually download; Rhythmbox just doesn't properly recognize that it's successful.  That bug *does*, however, also involve a server that doesn't provide the desired information through a HTTP HEAD query (albeit a successful one).

Modifying Rhythmbox to fetch the file even if getting its status failed would probably fix both bugs, however.

This bug is also present in HEAD.

This was originally filed as Debian bug 412416 (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=412416).