Sony is moving to make its music management software <A HREF="http://news.zdnet.com/2100-9595_22-6070936.html?tag=zdnn.alert">compatible with Apple Computer's audio file format</A> in the latest evidence of Apple's dominance in digital music. The behemoth Japanese conglomerate, which once controlled the portable music market, announced Tuesday that the company's data compression technology would be compatible with a number of rival formats, including Apple's format of choice, AAC. In the past, Sony has fiercely held to its own Atrac system. By switching to a technology that supports AAC, Sony appears to be acknowledging Apple's dominance in the digital music playing market, say analysts.