Posted 2012-February-04, 16:04
I think it shows a minimumish hand with diamond stop(s).
But I suppose it depends on the meaning of the 2♦. If you play that an opvercall is normally a 5 card suit, and a cue of 2♦ shows a good 3 card support, as is probably common, then I think 2NT describes the hand perfectly. "Careful, I have only 4 hearts". I don't see why it should be a game try.
If the 2♦ shows 4 card support, then I think 2NT should show a balanced game try with diamond stop(2) suggesting that 3NT may be better than 4♥, and of course this hand is not good enough for that.
If 2♦ is completely vague as to meaning, or shows a diamond guard, then 2NT means a minimumish hand with diamond stops.