Updates after adding a role

I have a W2k3 server which has been thru the following.

1. Installed 2K3.
2. Installed SMTP/POP3 server role.
3. Updated server with all critical updates available at the time.
4. Uninstalled SMTP/POP3 role.
5. Reinstalled SMTP/POP3 role.

My question is: If there were updates which affected files used by the
SMTP/POP3 role, did the newer files get overwritten when I did the reinstall
since I was required to insert the original 2K3 CD ?

If so, what should I do to "re-do" the updates ?

Thanks