can't work on armoured keyring

[Michael Nahrath]

This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--------------enigFFCC152A1BB891F6F764CD82
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

I downloaded a community's keyring from a website. It is ASCII-armored and
served via http: as 'application/pgpkeys' according to RFC 3156.

Unfortunately I get errors whenever I try to work on this keyring without
importing it. You may try on your own:

$ gpg -a --export 5B0358A2 99242560 > test.gpgkey
$ gpg --no-default-keyring --keyring ./test.gpgkey --list-keys
gpg: [don't know]: invalid packet (ctb=2d)
gpg: keydb_search_first failed: invalid packet
$ gpg --no-default-keyring --keyring ./test.gpgkey --check-sigs
gpg: [don't know]: invalid packet (ctb=2d)
gpg: keydb_search_first failed: invalid packet

Nevertheless
$ gpg --list-packets ./test.gpgkey
works fine.

Seems like GPG (same behaviour in all versions from 1.06 through 1.2.2rc2)
is unable to deal with a keyring if it is ASCII-armoured.

Is this	* a bug?
	* a known limitation?
	* technically neccesary?

We still would like to provide this keyring in a form that was suitable to
do WoT-annalysis etc. without further modifications.
Do we have to provide it in binary form for this?
What is the correct MIME-type for a binary keyring file?

Greeting, Michi

--------------enigFFCC152A1BB891F6F764CD82
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.2rc2 (Darwin)
Comment: http://www.biglumber.com/x/web?qs=0x9A4C704C

iEYEARECAAYFAj6ljLAACgkQ19dRf5pMcEwifgCgj7b6wc6suojxmuD1FXTjFjem
dcoAoMA70m4uENmyJvOBC8G3981iuR2m
=ES47
-----END PGP SIGNATURE-----

--------------enigFFCC152A1BB891F6F764CD82--