This is completely standard, right? 3 dollar rebuy on stars

[redmarion]

It depends! Seriously!

What range of hands do you think the UTG player would make this play with? [AA], [KK], [QQ], [JJ], [TT], {AK], & maybe [As with Q,J, or T] or [KQs].
Generally, a player that doesn't get out of line, has you crushed or you're only a slight favorite on a coin flip.

Do you really want to double up a player, that plays premium hands? You might knock him out, but you could make him a contender (with T50,000+ chips). [9,9] is the bottom end of the playing zone. It's a reasonable hand to see a flop with but 'all-in' is asking for trouble. If cards come out above [9] and you face significant action, you can fold for T6400 pre-flop investment. Why put in the extra T20,000 on a coin-flip gamble?