Totally don't mean to steal your thunder, cafuego, but I wanted to have the source available (AFAICT your source packaging only includes the finished binaries?). To that end, I forked the Ubuntu libnss-ldap and modified it to produce a libnss-ldap.so that's linked against ZCS' OpenLDAP libraries. This way it'll also be easier to track upstream (Ubuntu) changes and merge them into the modified packaging.
The package is libnss-ldap-zimbra, and it's available from:
deb
http://horde.net/~jwm/software/apt/ hardy zimbra
deb-src
http://horde.net/~jwm/software/apt/ hardy zimbra