Yes, sour grapes is the best IMO.
But its synonyms given here:
--------
sour grapes (n)
Synonyms: resentment, jealousy, bitterness, ill feeling, envy, ill
will, scorn
http://ca.encarta.msn.com/thesaurus_561588523/sour_grapes.html
---------
are flatly contradicted by Garner, and...