Hi,

When one receives en ical event and the user identity is not present in the attendee list, an error is triggered making replying to such an event impossible (the reply message not being even composed).  This patch replaces it with a warning.  This is necessary because one may receive (I just did) events that the organizer did not set up well and it is up to the user (not Emacs) to decide whether or not to reply to them.

Best regards,
C.