in Zimbra 8.0.6 NE we have the problem that sometimes when users create appointments and invite each other (Zimbra users only), the e-mail confirming the attendance to an appointment that is sent out gets sent out mulitple times. The problem is hard to track as I cannot reproduce it, no matter what I try. It does not happen very often, but it is very annoying for the users, as the get sent sometimes several hundred e-mails confirming the same appointment.

Does anybody have experienced the same problem? Any hints what could be wrong?