Hi,
I made a little script based on :
Mailboxes: Sharing vs. Relationships » Zimbra :: Blog
Here is a simple shell script to automate the procedure just replace YOURDOMAIN with your domain.
#!/bin/sh/
echo "Username of the Parent Account"
read parent
echo "Username of the Child Account"
read child
childid=$(zmprov ga $child@YOURDOMAIN | grep zimbraId: | cut -d " " -f2)
zmprov ma $parent@YOURDOMAIN +zimbraChildAccount $childid
zmprov ma $parent@YOURDOMAIN +zimbraPrefChildVisibleAccount $childid
Thanks,
Amir