Well there's good news for Linux users, XCP doesn't work at all.
I also found this tidbit on cdfreaks.com:
There may be an easier way but this is how I cracked XCP.
First, insert the disc (I used: A Static Lullaby) and hold the SHIFT key down for several seconds while closing the tray. I wait till drive activity stops before letting go of the SHIFT key. This bypasses the AUTORUN file.
At this point you can read the disc but can not see the audio files (only the data files). I was the able to use SONIC to easily make an "exact copy" of the disc. I did not try, but I assume this copy and any additional copies will work on all regular CD players.
The computer will not read the audio tracks on this disc either even when the SHIFT key is held when inserting. The copied disc does however have a gap on the outer part of the disc whereas the original does not.
I then took a Sharpie Pen and filled in the gap as well as a slight amount of the outer edge of the burned region. When I inserted the disc again (I did hold down the SHIFT key but I'm not sure it is needed at this point) the drive went spastic trying to read the data in the shaded in area but when the noise stopped, the data files were gone and I could read the Audio tracks. I ripped a copy to Windows Media player without difficulty. It sounds great and the player was even able to access the album info from the online source.
The great thing is I did not destroy my original. I may have been lucky to shade in just the right amount of area but it worked pretty well. My thought would be to shade a hair more of the outer edge of the burned area if the data files continued to appear. I definitely shaded the entire gap.
I know this is not very technical but it works. Look forward to seeing if this works for others.
This method sounds a bit trial and error, so it may not work with everyone. You will also need a beefed up drive and decent duping software to make a clone of an XCP disc. My buddy has a Foo Fighters which I hear uses XCP. I'll be sure to stay on this for everyone. My idea is different, I plan on making an image of the disc on my computer, removing the data bullshit from the ISO, and rewriting the TOC so it becomes a Redbook CD, then reburning it. Just like when duping old Dreamcast games...
Edit: Also, like with any hybrid CD-ROM, I may be able to use a simple hexadecimal editor to removes the extra bit encoded into the audio which encapsulates it into the XCP system, this bit prevents the audio from being ripped or played without the software. Without this bit, an XCP disc is esssentially neutered.