Jorge:
Here is how the jackpot works at our local Native American casino. I am not saying this is right or wrong, just that this is how they do it.
1. The jackpot was "seeded" by the casino in the amount of $5,000.
2. The rules (at least those I can remember) are; Aces full of tens or better beaten by quads or better. Both hole cards must play and trip aces on the board voids the eligibility of the hand for the jackpot. There are the other usual rules also, such as no electronic devices, no conversation between players and the like. For example, if one player would say to another, there is a jackpot possible, don't bet or even just possible jackpot, that could void the hand.
3. One dollar is raked for the jackpot as soon as the flop is dropped. No flop, no jackpot rake. This dollar goes into a separate jackpot box. The regular rake is taken AFTER the jackpot.
4. 25 cents of each dollar raked is held back to fund the next jackpot. Initially this 25 cents was used to repay the casino for the original seed money. The published amount of the jackpot DOES NOT include the amount of the reserve. ONLY the actual amount to be paid out is published.
5. If the jackpot is hit, 40% goes to the 'loosing hand', 20% goes to the 'winning hand' and the remaining 40% is split between all players at all holdem tables regardless of the game. Non holdem games are NOT ELIGIBLE and do not contribute to the jackpot. Mixed games are NOT ELIGIBLE as well.
That is what I remember off hand. As I said, I am not saying this is the right way or the wrong way, just the way it is done here.
Chet