[turba] Shared Address book and virtual hosts

[gcrothers]

I have set up the address book using mysql so that there is one shared to
all users and another that is the users private book,

However the shared address book is now visible to anyone with a valid horde
login account.
When I run this in an environment with different virtual hosts all users
have access to this common/public address book.

Has anyone implement a shared address book that can be restricted by login
domain ?

I was thinking about trying to use ldap as the book and doing something with
that.

Any ideas?

tia
garry crothers