music problem on EVERY phone? take a look, regarding music compatibility

Hello,

Many phones now support many types of audio. I use the wma format. Many of these audio formats are always being updated for example, microsoft keeps updating the wma and currently it's at series 9 with the pro version at 10. (i'm talking about the music version not the software.)

My phone is currently the w595 and sony ericsson says it supports several wma types including 9 series. my question is, as the versions increase, will the phone stop playing these new versions? I.E. Will i need to update my phone software and risk losing a lot of things like java apps or alternatively, will I have to buy a new model phone?

thanks,