wp caching to use with zend?

Yes, but with certain workarounds depending on the version of WP Object-Cache you're using. Like I explain in my other reply, we have three different "editions" of object-cache.php - which are you referring to?
Well I'm not referring to any of them in particular; it's just that I know my host uses zend, and not xcache or eaccelrator. So I figure, you've published a version for xcache, one for eaccelerator, but no version for zend, so that's why I ask how to do it for zend.

But if I'm gonna choose which version to adapt to zend, it'd be the file-based one, since I'm familiar with how it works... well, I'm familiar with how it worked in wordpress pre-2.5.

But to adapt the filebased one for zend, would I have to muck around with the server at all? I'm on shared hosting, so I don't have complete access.
Ah, you're referring to creating a new caching backend to take advantage of Zend's caching....

Well, you can use XCache or eAccelerator alongside Zend, but you'll have to reconfigure the server (you can't do that as a shared-host user). The file-based caching implementation can be used out-of-the-box without any special permissions or settings for all types of accounts - shared, dedicated, or otherwise.

As for creating a new module to take advantage of Zend - I have no idea on the matter, but will look into it.
Please have a look at Zend Framework: Documentation

It explains how the Zend framework handles caching. Basically, it doesn't actually cache anything itself, only offers a gateway to an already existing PHP caching engine installed in the background.

It supports indirect caching to APC, Memcached, or Files; all of which already have direct caching implementations written as wordpress object-cache extensions and are available for download.