[ale] collaborative work environment

[John Pilman]

I am looking for a set of tools to help in an upcoming project.  I
will be working on a team of four to eight people all of whom work in
different cities.  Our normal routine is to spend a lot of time on the
phone, two parties at a time.  We have a common file server, but
document control is difficult since everyone gets copies the documents
and modifies them locally.  Of course we use email for correspondence
and document archiving as well.  Our documents are mostly the word
processor and spreadsheet varieties.  We do have some drawings which
are usually shared as PDFs.

I would like:
a group chat which archives conversations so newcomers can review the
past conversations
a file server which
     marks editable documents as 'Checked Out because someone is
editing them' or 'Available to be edited'
     tracks changes and/or keeps chronological backups
     notifies users of added or updated documents

It would be nice to have:
    online editing of word processor and spread sheet documents
    a Linux based solution that I can host in house

Our word processor documents have objects inserted, jpegs, usually.

I have looked a little at Google Wave and irc for the chat part, but I
don't have much experience with either and would like to get your
ideas.
TIA
...John