I am using SendInviteReply to update the status of an event but it does not seem to be updating it. Below is the XML request and response:

<SendInviteReplyRequest xmlns="urn:zimbraMail" echo="1" html="1" id="361-360" compNum="0" verb="ACCEPT" updateOrganizer="TRUE">
<e t="t" a="c80calendar@gmail.com"></e>
<e t="t" a="c80calendar@gmail.com"></e>
<mp part="" ct="text/plain" body="1">
<SendInviteReplyResponse xmlns="urn:zimbraMail" invId="361-475" apptId="361" calItemId="361"></SendInviteReplyResponse>

Am I doing something wrong?

Thanks for the help in advance.