TSGL: Another Time Related Question "Internet Time"

[Glen Bigelow]

I'm running XP Home SP2.  When I go into "Adjust Date/Time", I have 3
tabs---"Date & Time", "Time Zone" and "Internet Time".  When I click on the
"Internet Time" tab, I see a box that I can check, titled "Automatically
synchronize with an Internet time server.  Then there is a pull-down box
where you can enter the time server that you want to use.  It defaults to
"time.windows.com", but you can change it to whatever time server you want
to use.

Now, here is my question.  I have a friend who is running XP Pro SP2 and
when she goes into "Adjust Date/Time", she does not have the "Internet Time"
tab.

Does anyone know why one version of XP has it and the other doesn't?  And
with that in mind, is there any way to add that functionality to her system?

Glen B.
Sacramento, CA