I have two separate Zimbra servers, using two separate domains. Let's call them server01.example.com and server02.example-zcs.com. I'm hosting internal staff on server01 and external accounts, hosted accounts, on server02. I would like to be able to share the GAL of server01 with server02, so that our hosted customers can share their address books and calendars with our staff, who are on server01. Is this possible to do without building a cluster? If so, any ideas/assistance I could get to achieve this would be greatly appreciated.

Thanks in advance.