Howto download and send a secured file using default email c

Hi,
I have an application that requires a login to be able to view secured
documents and need to give the users the option of emailing the
document using their default email client, in this case Outlook.
The Web server is Debian
Basically I need to know, how to have an action, that will download the
file to a specific location on the client system then bring up Outlook
with subject and attachment details completed with something like this
mailto:[email protected]?subject=SUBJECT&attachments=““C:
\temp\THEDOC.TXT””

Actually the whole reason for wanting to use their default mail client
is to have access to their address book so that they can choose from
there who the recipient of the email is to be. So better still would be
for the user to be authenticated through Ruby/LDAP then somehow get to
the Exchange Server and be able to populate a select list of addresses
from their Address Book. Maybe something like SAMBA could be used to do
this.

Thanks,

Bruce