We are currently having problems w/ IE4 and IE5  regarding scrolling.  We have a large production grade applet (larger than most browser windows using the latest swing components and the 1.2.2 plugin) which when embedded inside the html page causes massive scrolling (component repainting) problems when the user tries to scroll with the default browser scroll bars or resize the browser.  The repaint problem basically causes a large chunk (sometimes multiple strips) of the applet to become non-visible and basically useless.  This problem can be reproduced w/ any visually large applet w/ swing and occurs all the time with Internet Explorer 4+.