I can see Google is implementing the Portable Contacts API for developers to fetch a user's contacts. That seems like exactly what I want to do and I especially like the fact that the protocol is open and through it I can support more than just Google.

What I'd like to know is whether there is a library for PHP that implements this protocol, as I don't feel like writing one from scratch / reinventing the wheel.

I wouldn't generally post such questions which could be answered by simply googling, but I've done my googling on the subject and can't seem to find any relevant info.

BTW, I don't use Zend, so please don't suggest that to me, unless it's the only way possible.