Registry changes and WM 4.7.0106

About a year ago, a large company I'm consulting for rolled out to all of
their W2K computers a version of Messenger 4.x with Exchange IM support.
They used a custom installer which made six registry changes, specifically:

Under HKCU\Software\Policies\Microsoft\Messenger\Client\ :
1) Set {9b017612-c9f1-11d2-8d9f-0000f875c541}\DisableAutoUpdate to 1.
2) Set {83d4679f-b6d7-11d2-bf36-00c04fb90a03}\Disabled to 1.
3) Set DisablePC2PCAudio to 1.
4) Set DisablePC2Phone to 1.
5) Set PreventAutoUpdate to 1.

6) Added ExchangeConferencing key to
HKCU\Software\Microsoft\Office\9.0\Outlook.

The third, fourth, and sixth registry changes were made to disable those
features in this enterprise environment. The remaining three changes appear
to have been made/added to prevent the user from receiving update
notifications.

The company is now in the process of making preparations to move to WinXP
and the 4.7.0106 Windows Messenger client, which also supports Exchange IM.
I've been tasked with verifying that these six registry changes are still
applicable under WinXP/WM and haven't been changed.

Any suggestions on how to proceed? BTW, AD has now been fully implemented
within the company; could these settings be made via Group Policy?

Chris