Yes a plugin would be needed. However from a quick glance I don't think either of the linked libraries will help. The icecast protocol will put metadata into the MP3 stream every X number of bytes (with X being controllable via said header). To properly support it, you need to read the stream yourself, cut out the meta data and handle it and then send the raw MP3 stream on to the player.
Implementing this might be quite difficult in PHP because of the long running nature of a stream and the problem of pushing the meta data to the browser. It might actually be easier in JavaScript.
Source: I once implemented an icecast client for Android