There's already a bugzilla bug for this...
I have also reported this through the support portal. Just curious if anyone else is running into weirdness with the free/busy search functions.
We have at least one user at our site that has noticed some strange behavior with free/busy searches. He has maybe a total of 10 events a week in his calendar, none of which ever last more than an hour or two.
When he goes in to use the free/busy tool to schedule meetings between himself and his co-workers, his calendar shows him busy beginning at 2AM August 26th through 2AM August 31st. Then free over the weekend. Then beginning 2AM next Monday morning through 2AM next Saturday morning he is busy again. Then free over the weekend...and on and on...
So looks to me like 2 things are going on.
First and most importantly, it seems for some reason that his calendar is marking him busy (all day event) through the work week.
Secondly...since we're in the Central time zone...it looks like Zimbra is not calculating the time zone correctly and is using Pacific time when calculating that he's busy all day.