Hi,
That's a good question.
At the moment, you can use Akonadi to set-up 'traditional KDE addressbook' resource which will effectively get it to use GAL.
For your contact folder/s, you will need to await KDE SC 4.5 to be released (due August, or try the Beta released next month).
This will include a GroupDAV resource. Zimbra also now has GroupDAV functionality.
Read more here:
https://www.zimbra.com/forums/users/...e-kontact.html
(You can already connect Akonadi to Zimbra's contacts by using VCards, but these will not be stored locally and Akonadi will have to reload the contacts when you go online, also they don't sync very well and you are at risk of losing contact data - so best avoided. GroupDAV also uses VCard but the contacts have unique identifiers (UIDs) so that they can be synced).