Federal prosecutors this week leveled conspiracy charges against two men who allegedly used an exploit against a line of video poker machines to win hundreds of thousands of dollars in unearned jackpots.

John Kane, 52, of Las Vegas, and Andre Nestor, 39, of western Pennsylvania, allegedly pulled the caper in Las Vegas casinos over six weeks in the Spring of 2009. According to a criminal complaint filed in Las Vegas (PDF) on Monday, the men would make small bets over and over again until finally winning a hand, then use a special button sequence to change the credits to a higher denomination and "access the previous winning hand of cards," triggering a jackpot.

It was Kane who first learned of the exploit, and after testing it, contacted his friend Nestor in Pennsylvania and told him to come to Vegas, the complaint alleges.

A separate state case accused Nestor of pulling the same hack at the Meadows Racetrack and Casino near Pittsburgh, Pennsylvania, where he allegedly won over $400,000. He was about to begin a trial on those charges on Monday. Instead, the FBI intervened to arrest him in the new federal case in Las Vegas.

Before he was hauled away from the Pennsylvania courthouse, Nestor told WTAE-TV that what he did was the equivalent of counting cards in blackjack—he'd found a way to get an edge on the house, and, naturally, exploited it.

"I'm being arrested federally for winning on a slot machine," he said, in apparent amazement. "It's just like if someone taught you how to count cards, which we all know is not illegal. You know. Someone told me that there are machines that had programming that gave a player an advantage over the house. And that's all there is to it... Who would not win as much money as they could on a machine that says, ‘Jackpot'? That's the whole idea!"

The men were part of a ring of at least four lucky gamers, according to local news reports. Posing as high-rollers at the casinos, they often had to persuade the casino staff to open up the machines and activate the "Double Up" option—a prerequisite to exploiting the bug, the Las Vegas Review Journal reports.

The game was reportedly the Draw Poker machine made by Reno-based International Game Technology. The two defendants are accused of conspiracy to commit computer fraud.