Cannot sign key with expired signature

[Sascha Silbe]

One of my friends has prolonged his key, so I want to prolong my signature 
on it, but GnuPG refuses to sign that key again.

His key and my expired sig on it:

=== Begin ===
sascha@cube:~$ gpg --list-sigs CE9DDE57
pub  1024D/CE9DDE57 2001-03-12 Caspar Bothmer <caspar@cbothmer.org>
sig 3       CE9DDE57 2001-03-12   Caspar Bothmer <caspar@cbothmer.org>
sig         6135C35B 2001-03-21   Old key - please use 74E5CF87 instead
sig 3     X 74E5CF87 2002-06-13   Sascha Silbe <sascha@silbe.org>
sig 3       CE9DDE57 2003-03-13   Caspar Bothmer <caspar@cbothmer.org>
sub  2048g/A2366D02 2001-03-12 [expires: 2003-03-12]
sig         CE9DDE57 2001-03-12   Caspar Bothmer <caspar@cbothmer.org>
sub  2048G/3ECA1531 2002-09-09 [expires: 2004-09-08]
sig         CE9DDE57 2002-09-09   Caspar Bothmer <caspar@cbothmer.org>
=== End ===

Trying to sign the key again:

=== Begin ===
sascha@cube:~$ gpg --sign-key CE9DDE57

pub  1024D/CE9DDE57  created: 2001-03-12 expires: 2005-03-12 trust: m/-
sub  2048g/A2366D02  created: 2001-03-12 expires: 2003-03-12
sub  2048G/3ECA1531  created: 2002-09-09 expires: 2004-09-08
(1). Caspar Bothmer <caspar@cbothmer.org>

"Caspar Bothmer <caspar@cbothmer.org>" was already signed by key 74E5CF87
Nothing to sign with key 74E5CF87
Key not changed so no update needed.
=== End ===

Is this a bug or am I just missing something?

CU/Lnx Sascha

-- 
Registered Linux User #77587 (http://counter.li.org/)

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