Is there any PHP (+ xml?) equivalent (or similar) for this awesome .net library?

[Firefox Wins]

(09-16-2010 01:35 PM)Firefox Wins Wrote:  ...This can be game-changing for data-exchange and app-level data interop...

...What I'm looking for does *not* even need any RSS/Atom/xml; I'm interested in the two-way sync with no concept of a "master" copy.

• Has anyone ever seen a way to do that with PHP?
  

Thank you.

Thanks for trying to answer, Zinga:

(09-16-2010 03:33 PM)ZiNgA BuRgA Wrote:  ...You seem to be highlighting the decentralised part a bit, and I don't think you fully understand what it really means...

True two-way sync with no concept of a "master" copy, is (both) error-prone, and valuable + powerful, if done properly.
I do understand well enough to know I want to learn more.