Reference:
Multitouch touch-pad support for Linux laptops.
Link to original IBM article entitled "Add multitouch gesture support to a TouchPad-equipped laptop" at end of above article which reviews it and illustrates a use of it with a Youtube video link regarding semi-reliable pinch and open-pinch gesture provided by the perl script from the IBM article.
You can download the perl script from the download link at the bottom of the IBM article.
-- Tom