Shared contacts from outlook

[Narev]

Hi we are trying to setup a testcase with zimbra in which we want to synchornize our zimbra server with our own CRM and with our email program outlook. We want to be able to create new contacts in every one of these apps. To achieve this i figured we could create a "sharedcontacts" account that has an adress book that is shared with every user in our company but i just noticed that it is not possible to directly add users to this adress book in outlook. Is this possible, if not, how could we bypass this or how can we use the GAL of zimbra from outlook?