why must gnupg user-id "real names" be at least 5 characters long?

[tav]

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rehi all,

when generating a new key, gnupg insists on the "Real name" aspect of
the user-id to be at least 5 characters long:

	Real name: tav
	Name must be at least 5 characters long

why is this?

can i just comment out:

    else if( strlen(aname) < 5 )
        tty_printf(_("Name must be at least 5 characters long\n"));

or, is there some need for the "Real name" string to be that long?

in the past, i have overcome this by providing "tav -" as my name, then
the user-id becomes "tav - tav@espians.com", but i would like to create
a key with just "tav" now...

also, this leads onto the question of what the user-id is used for?
could someone give me a brief summary please? (apologies for not reading
the openpgp spec to find out. the 70 odd pages is a bit much for me.)

-- 
best regards, tav
tav@espians.com

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