iTunes: Submitting CDDB info

I've typed in the album and track info for several of my CDs that I've
read into iTunes.  They're commercial CDs that CDDB doesn't know
about.  The obvious next step is to do my civic duty, and submit the
info to CDDB.  The Itunes Help stuff says that the magic incantation
is Advanced -> Submit CD Track Names.  But it's greyed out and doesn't
work.  I've poked around in the Help info, but found no clues.  I've also
tried random iTunes tweaks, including filling in the info fields I don't
understand with some dummy strings.  Nothing works.

So can iTunes actually be used to submit this info?  If so, does anyone
know how to make it work?