http://www.jetaudio.com/news/details_21.html

On Feb 18, 2003 the new jetAudio 5.01 Basic and Plus Upgrade versions were released. Now the freeware player supports MPC playback (beta stage), while the upgrade for U$ 29.00 also enables mp3PRO and MP3 encodings. Another new freeware feature is Ogg Vorbis streaming support, both receiving and sending probably with the included jetCast:

http://www.jetaudio.com/download/index.html

They even managed to create a FAQ section on their website where some details of the different versions and resulting misunderstandings are explained, for example:

http://www.jetaudio.com/support/faq_jetaudio.html