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I would not describe you jamming here a squeeze play. The action before your jam is call + 3-bet. In order to be a squeeze play the order should be the opposite, so that the 3-better is squeezed between you and a caller. That would increase your fold equity.
When the SB 3-bets an UTG+1 raise followed by a call he should have a strong range. Unless he decides to squeeze you when the MP only calls (the action before the SB is your raise + a call, i.e correct order for a squeeze).
Remember that the essential idea behind a squeeze play is that you put pressure on a raiser by reraising him when he has to worry about both your reraise and a caller yet to act.
Having said that, jamming jacks for value might be good if you have reason to believe that your opponents are calling way too wide. In normal circumstances though jacks are not strong enough as a value jam and there are other hands that you can turn into bluffs.
