RealNetworks plans to release new software this week that allows songs purchased through its online music store to be played on Apple’s iPod — the first time a company other than Apple has sold songs with DRM (digital rights management) that will work with the popular device. The new technology, called Harmony, was created without Apple’s authorization. In April, RealNetworks chief executive Rob Glaser sent an e-mail to Apple CEO Steve Jobs, asking him to license Apple’s Fairplay digital rights management technology. Jobs never replied, so RealNetworks created Harmony, Glaser said.