check out iCalendar -
http://www.imc.org/rfc2445"From RFC 2445: There is a clear need to provide and deploy
interoperable calendaring and scheduling services for the Internet.
Current group scheduling and Personal Information Management (PIM)
products are being extended for use across the Internet, today, in
proprietary ways. iCalendar is an internet RFC that addresses
communication between calendaring clients. It defines a set of
objects and a method for writing those objects to a character output
stream. Any client which understands the iCalendar protocol should
be able to share appointment , to-do, and other calendar information
with any other calendar client or server. "
and vCalendar also at imc.org
its probably much more useful to stick to standards than whatever
the current version of a ms product does.
from for outlook2k
http://support.microsoft.com/support/kb/articles/Q257/8/24.ASP
"Outlook is designed for use with the Internet (SMTP, POP3, and
IMAP4), Exchange Server, or any other standards-based communication
system that supports Messaging Application Programming Interface
(MAPI), including voice mail. Outlook is based on Internet standards
and supports today's most important e-mail, news, and directory
standards, including LDAP, MHTML, NNTP, MIME, and S/MIME, vCalendar,
vCard, iCalendar, and full support for HTML mail."
