I think you are talking about handwriting. With this you can draw with the mouse.
For
MSN 6.2 see
Handwriting/Ink all you need to know...
The handwriting is already built in in
MSN 7, so for that you don't need the full plugin. If your OS is able to handle handwriting and it doesn't work: install
Ink redist and make sure you install "for all", otherwise it won't work. Exit MSN before you install and restart afterwards.
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