finally upgraded to zimbra 8, everyone misses chat, so...
basic zimlet attached to use https://conversejs.org/ as a replacement chat for zimbra 8
note that this is not ready to go, you need to open the zimlet and edit where your prebind service is and some other things in converse_zimlet.js
I am using it with ejabberd which is using zimbra ldap so anyone that logs in can prebind. It helps to have everyone in a group shared roster too so noone has to add anyone.
I have overridden some of the default conversejs css to make it fit in a little better with zimbra, but still a work in progress. Compared to the old zimbra im it does not save chat logs or flash browser title, but it does do multi-user-chat and it looks better IMO
Hope this helps some of y'all I don't plan to maintain or support this, but hopefully if anyone makes this better, post back here.