[Davical-general] accepting invites with external users not working

[<pcc...@gm...>]

Hello,
I have davical 1.1.3.1 installed on CentOS 6.6  Users are on Mac OS X
running the stock Mac Calendar app

So far things seem to be running well, but noticed that some events where I
have been invited along with other users, I am unable to respond at all
(Maybe, Decline, Accept).  When I go and click a response, the calendar
event changes from light gray to solid black in the Calendar app, but then
switches back to light gray.  It looks like it's trying to process my
response but ultimately does not keep my response.

It looks like when all the invitees are users of the davical server, I can
respond just fine.  It seems only when there is another invitee that is not
on the davical server (an external user) that this is where I experience
the above issue.

I do see errors in the web log. I can provide parts or whole as needed, but
didn't want to just put up a bunch of lines of log info to start out.

Has anyone else seen this issue and/or figured out how to resolve?  Thanks.