Vista - bulk mail enable contacts for existing AD users

Hi

I am really hoping someone can help me.

I need to do 2 things:

We have an exchange server 2007 which our teachers and other staff use and
students who use Novell Groupwise 7. All users have AD accounts and the plan
is students will use groupwise with their AD username and password. Staff
need to be able to see students in the outlook global address list even
though the mailboxes are not on exchange, to summarise I need to create a
mail enable for an existing contact in Exchange pointing to their email on
Groupwise.

One of the issues is our usernames are setup as
yearfirstname.surname@newsgroup and for users to login to groupwise
their username needs to be yearfirstnamesurname@newsgroup (just
removing the dot)

I have managed to export our AD users from an OU and export it as a CSV and
removed the . but now need to insert this back into ad and change the
attribute for email.

At the moment for each student some have an email address in the email
attribute in AD and some don't. I need to somehow insert some information
into this attribute box which is username@newsgroup as well as bulk
create the mail enabled contacts for existing AD users.

Can anyone point me in how I could do this with a CSV file. If it can be
done I would really appreciate some assistance on what columns I need in the
CSV. I have got most tools available to me such as powershell, exchange
management shell, Quest PowerGUI, AD modify and CSVDE. If I could use any of
these tools to assist me it would be great.

I am aware that once all mail enabled users are in I need to run the
following command in Powershell which updates the global address list for
Outlook.

update-globaladdresslist -identity "Default Global Address List"
-domaincontroller {domain controller name}

Can anyone help?