calendar and file server (sort of a repost)

[Matt Price]

Hi folks,

In an earlier thread I asked about calendar and email syncing, but: 

I just found out that a research group I work with has some money to
replace their current IT set up and are thinking about installing
microsoft exchange and I guess some kind of ms file server (I'm
ignorant about MS, so I don't know the details).  I'd like to see them
instead get a ubuntu server that handles mail, calendaring, and file
sharing.  As I understand it, they mostly use ms outlook for both mail
and calendaring.  If poss I'd like something that will also
sync/interact with evolution (then I could participate) and is also
compatible with my palm (right now an old Palm V, but maybe I'll get
something new and fancy -- treo or a Palm TX ore a linux
smartphone...).  

My question:  is there an option which will not disrupt their workflow
too severely?  And what options particularly should I look into?  

Thanks much for your help.  

Matt