I've also filed a support request for this but I was wondering, while the Zimbra engineers are looking into it - has anyone else experienced this behaviour:
I'd be grateful for any reply. I'm quite puzzled that creating a contact with just an e-mail address tagged "business" doesn't show up in the system at all (neither auto-complete nor when clicking the TO button in compose view). In fact those e-mail addresses tagged as "business" are completely ignored throughout ZCS.We initially installed 5.0.18 but recently updated to 6.0.1. Since then my users have been complaining that the auto-complete function when filling in the receipients of an e-mail (TO field) does not work properly anymore.
Through testing on my own account I was able to establish that new contacts created with just a "business" e-mail address will not show up during the auto-complete process or when clicking on the TO button in the compose e-mail screen. Also the auto-complete feature will just search last name and e-mail address for matches but not the first name.