Shares in Digital River did some fancy jumping on Friday, caused by the rumor that the company’s software would be used by Apple for enabling sales of downloadable games onto the next-generation iPod.

It would be a break with tradition for Apple, which has kept iPod digital commerce routed strictly through the iTunes Music Store. It’s not out of the question, though; the deal with Hewlett-Packard to produce HP-branded iPods was a departure from standard operating procedure, and that happened.

It’s an intriguing concept. The iPod already comes pre-loaded with four games, all of the simple time-killing variety. Apple’s not going to give the iPod a major hardware/interface redesign for the purposes of gameplaying, so I’d expect any games they try to seel would be of a similar vein (and very much like the game-lettes sold by wireless providers on mobile phones).