Rule question

[dana33]

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Pre-flop... someone raises before me but I don't see him to it... I throw a chip in thinking I'm limping... Other players tell me that I've under-called... I realise my mistake and say that I didn't see the raiser raising & want to take my chips back and fold instead... am I allowed? or am I forced to call for the full amount?

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This is really funny, because the exact same thing happened to me a couple of days ago playing 3/6 at the Aladdin in Vegas. I was sitting to the dealer's immediate right, I checked the turn, the guy to the dealer's left bet, and the guy to his left raised -- which I did not see. (My excuse, to the extent I have one, is that I have played mostly on the internet and am still getting used to the flow of a live game.) I put out $6, and the dealer said there was a raise. I asked if I could still fold, and the dealer hemmed and hawed, finally saying it was probably OK. But the raiser raised a stink, so we called over a floor man who said that as long as the chips were in front of my cards, I was committed to calling.

I didn't know if this was a proper ruling, but at the time I was pissed off at myself for not paying attention, at the raiser for making a stink, and at the floorman for ruling against me. Rather than play on tilt, I picked up my chips and went to cash out. At the cashier's cage, another player from the same table told me the ruling was a bad one, that this sort of thing happens all the time, and they always let the person keep his bet and fold.