Parental Controls Question

I have a young daughter who uses a vista ultimate PC.

I've set up parental controls, but I'm most concerned about Instant
Messaging, web cams, and IM chatting with strangers, etc...

I don't want to restrict her use of it, except for the logon hours allowed.
But I do want to use the Instant Message Tracking in the Activity Viewer.
She's using Windows Live Messenger, which I should assume be compatible with
this feature of Vista, yet the Activity Viewer for Instant Messaging is not
showing any tracking of IM's or Webcam usage.

If I log into her account and set the Keep records of conversations in
Messenger, there's nothing preventing her from turning this feature off when
she logs in.

Can anyone give me some ideas on how to take advantage of the Instant
Message tracking in the Activity Viewer, without allowing my daughter to
change the settings of her own Messenger profile to prevent this?