gpg: can't put a policy URL into v3 (PGP 2.x style) signature

[Atom 'Smasher']

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Hash: SHA1

> You're presumably getting this error not because you can't clearsign,
> but because you can't have a policy URL or notation in a v3 key.
========================

but i should be able to include a policy URL in a data signature, and i am
using a v4 key.

key with subpackets (v4):
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
$ gpg --list-key smasher
pub  1024D/3D7D41E3 2003-10-04 Atom Smasher <atom at suspicious.org>
sig 3       3D7D41E3 2004-02-22   Atom Smasher <atom at suspicious.org>
uid                            Atom Smasher <atom at smasher.org>
sig 3       3D7D41E3 2004-02-22   Atom Smasher <atom at suspicious.org>
sub  2048g/1E88BF71 2003-10-04 [expires: 2005-01-26]
sig         3D7D41E3 2003-10-04   Atom Smasher <atom at suspicious.org>
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


trying to include a policy URL (XYZ) into a clearsigned message tells me:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
$ date | gpg --sig-policy-url XYZ  --clearsign

You need a passphrase to unlock the secret key for
user: "Atom Smasher <atom at suspicious.org>"
1024-bit DSA key, ID 3D7D41E3, created 2003-10-04

gpg: writing to stdout
- -----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Fri Apr  9 15:08:54 EDT 2004
gpg: can't put a policy URL into v3 (PGP 2.x style) signatures
gpg: DSA signature from: "3D7D41E3 Atom Smasher <atom at suspicious.org>"
- -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.4 (FreeBSD)

iD8DBQFAdvTKnCgLvz19QeMRAiZNAJ44xLs1X8J4oaXGF0PcVUZZ6unjFQCfQeGk
Aoyqh/skv/lanScpeVzNiSA=
=UQ4V
- -----END PGP SIGNATURE-----
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

there error is:
gpg: can't put a policy URL into v3 (PGP 2.x style) signatures



	...atom

 _________________________________________
 PGP key - http://atom.smasher.org/pgp.txt
 3EBE 2810 30AE 601D 54B2 4A90 9C28 0BBF 3D7D 41E3
 -------------------------------------------------

	"Patriotism is your conviction that this country is superior
	 to all other countries because you were born in it."
		-- George Bernard Shaw
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.4 (FreeBSD)
Comment: What is this gibberish?  -  http://atom.smasher.org/links/#digital_signatures

iD8DBQFAdvX8nCgLvz19QeMRAtVBAKCRJ5gK828G9SWzroVTXt6ZFutHwACeLwQl
158KflfpLqXH21d0WjXKpEc=
=zPI7
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