Restrictions on key versions for rpm?

[Bruno Wolff III]

I was trying to import an old pgp key into rpm and it is failing without
a useful error message about why. The key needs idea, but I have that
installed. I don't know if there is a bug, a limitation or user error.

[root at cerberus rpm-gpg]# rpm -vv --import gpg-pubkey-bruno
D: opening  db environment /var/lib/rpm/Packages create:cdb:mpool
D: opening  db index       /var/lib/rpm/Packages create mode=0x42
D: locked   db index       /var/lib/rpm/Packages
error: gpg-pubkey-bruno: import failed.
D: closed   db index       /var/lib/rpm/Packages
D: closed   db environment /var/lib/rpm/Packages
D: May free Score board((nil))

I exported the key with:
gpg --export --armor

The key is:
-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.4.9 (GNU/Linux)

mQCNAi4QRoMAAAEEANdxLMwIrLVJj298ORThEmEELSkHRNhtR8afomd8dKJOLE3r
PKB4maGwQoOQPcOvATBhtQbOGLw9aLYdqOBqXi2o33y89TilRAneH0fKIRVDhwXr
bpT+JBwU4FNRXyoQ0jJInIPnellqMVBxVtjajiWhZ8/qKOz14auclAPcXnktAAUR
tCBCcnVubyBXb2xmZiBJSUkgPGJydW5vQHdvbGZmLnRvPokAlQMFE0WdzOKrnJQD
3F55LQEBTC4EAIHVLVDxBARGpnT7u3yT9Nj0qoUISCnqrkOICRgr3a6i6JQpmt+V
WG36wtch0YrcJZ6AB6ugGPdAt5zQ1KJkNCW+JfgJRVFSJV/3kGJVqRGmHmhFK0uV
dLsFsGOFRQKu+Rj0sJ9XQqtToODOTRSg76ngn4ysgh1ywatLimWn8ezD
=S/q8
-----END PGP PUBLIC KEY BLOCK-----