Both my 2004 Hemi Durango and my 2006 RT charger did this exact same thing. Not always but whenever they had been driven for a while. No prior warning, they just died while driving. I then turn the key and they start right back up. Never did find the problem. The dealer said he sees it all the time and it's just a computer glitch that corrects itself.
Probably a lie just to get me to leave but it sure seems like something a computer would do.