Strange signatures

[Kurt Raschke]

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I recently checked my key to see who'd signed it, and I found one of my user IDs and one subkey had the following line in them:
[unexpected signature class 0x00]
Now, is this anything to be worried about, and if so, what do I do about it?  Furthermore, why would a subkey have it?  I thought people only signed the master key and all of its user IDs.

-Kurt

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-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.4 (GNU/Linux)
Comment: For info see http://www.gnupg.org

iQEXAwUBOoRZquAp5bSt9RqIFAM/hgP9Ha9Ald0TKdJp1kNbnWdi/s1AUUSUcdow
tc1eUvvZNalsc/MllaWoyAIpa/Igv8j0Cp15Yei2z7yc6uRyIlFoL0B4rHB0QLwA
Sy3J4Xrqm16m+dc3gQsyPdd0gM/H1PAnfjpp70Ofxc+fFyJz+9Cb6PxwzAT1Pxxz
UwqJGCD78MMD/2S98fptoWVktWacgNRL6LvfdRpYhT5M3BG62PzUVF7gzv4cTt+a
sSw9ZxRChutaCXd/gMQyxMwSR3AtSu2CBvck4jEelTJY+RaExp2l+j+rxNW13lBG
1H/gTKXOE/Tf0eUbBzvonO2GLbjqW/FZPjlSaHLYVBVK7R4VsWoKDQ64
=JYrZ
-----END PGP SIGNATURE-----

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