You need the CatDV MXF Option to enable the MXF and P2 Importers. With the MXF option CatDV will read MXF and XML camera metadata and automatically match up the video and audio tracks of P2 clips so you can play them as a single clip. You can also edit and export the P2 metadata in CatDV.
Unfortunately, right now the MXF Option is only available at the time of purchase of a networked installation, it's not available via the web site or as an upgrade on its own. We hope to change that soon, but if you need further information in the meantime please drop a line to firstname.lastname@example.org
You'll also need a suitable MXF codec from MXF4Mac or Calibrated to be able to play the clips or build previews from within CatDV.