This is very repeatable for me. If I create an appointment on my windows
mobile device (AT&T Tilt running WM6) and add an attendee, the attendee will
be sent a calendar appointment via pop/smtp mail from the WM6 device. The
appointment they receive will show up in their calendar at the date and time
the email was received, rather than the date and time of the appointment. I
have tried this with WM5, WM6 on two different devices (8525 and tilt) and
outlook 2003 and 2007.

If you have access to a WM5 or WM6 device and a PC with XP and outlook, and
pop/smtp mail accounts on both, please try this. Is there a patch that
addresses this issue?
Thanks in advance,
Wes