<A target="_blank" href="http://www.idonotes.com/IdoNotes/idonotes.nsf/dx/calendar-entries-in-Notes-8.5-conflicting-when-meetings-really-dont.htm">Chris Miller says there is a bug in the Notes 8.5 code</A> which makes calendar entries appear to be in conflict when they really aren't. The bug has been fixed in 8.5.2.