I don't think so. As long as each user has outlook, you should be
fine.
Instead of the provided outlook  webpart, maybe you should try this
instead:

http://support.microsoft.com/kb/q291407/

(works with outlook 2003 for sure, and likely 2000 as well).
It provides the HTML necessary to hit the Outlook object, and go at
any
folder (sent items, calendar, etc.) I created a webpart that has a
dropdown box with all the folders listed. Then, by adding a variable
to
replace "Calendar" in this line:

<param name="Folder" value="Calendar">

changed to
<param name="Folder" value="<%=FolderName%>">

you can navigate all folders. Plus, unlike the provided web  part, my
web part is not 'read-only.' Hope this helps!

just tested it...Only works for 2003

I believe my problem is the Form Based Authentication foisted upon us
by our Exchange team.

So much for Requirements Management.

Not that I know of..................

You do need to have Outlook on your clients.