MediaLab uses Internet Explorer as its web engine so it should act exactly as it does in IE. It should accept onkeypress events in the same manner as any page in IE would. However, one difference is that the HTML window within MediaLab will need to have the "focus". Your javascript programmer will likely be able to cause this to happen automatically but you can also do it manually to test it. For the test, try clicking on the HTML page once before the onkeypress function is to be tested. Otherwise, the keypress may go to the MediaLab shell rather than to the contained HTML page.