Shared address book between 10.7.5 server and 10.8.2 clients

Hi,

My company run a 10.7.5 Lion server. One of the services running is the shared contacts.

I recently added two new iMacs on the network that came with 10.8.2 Mountain lion.

On those two machines I couldn't manage to add the shared contacts, and was wondering if either the method to declare it had changed, or there was a known problem.

The procedure I used to connect to the shared contacts under 10.7.5 was the following :

- In system preferences, open "mail, contact, canlendar"

- add a new "other" account at the bottom of the list

- select "add an OS X Server account" and click "create"

- the server IP would show in the next window where it could be selected.

My problem is : on both iMacs running 10.8.2, the server is not shown.

Has anyone encountered (ans hopefully solved) this before ?

Thanks for your time

Theo