Leaving comments with subkeys?

[gnupg at lists.grepular.com]

If I have more than one signing subkey in my keypair, is there a way of
advertising the purpose of each subkey with the public key that people
download? Eg:

This subkey is for signing email only
This subkey is for signing sourcecode only

I've considered generating an entirely separate keypair and then
cross-signing them, but that seems inelegant.

-- 
Mike Cardwell https://grepular.com/  https://twitter.com/mickeyc
Professional  http://cardwellit.com/ http://linkedin.com/in/mikecardwell
PGP.mit.edu   0018461F/35BC AF1D 3AA2 1F84 3DC3 B0CF 70A5 F512 0018 461F

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