While surfing the net I came across a download link to target a file called divx5.zip. Curious I was so I downloaded it and took a look. Included is the divx.dll version 5, dated 26th of February 2002... Unconfirmed information has it that DivX 5 will be officially released on Monday.
Unfortunately it seems that the DivX decoder filter file is missing which would be divxdec.ax. I assume that the .dll alone won't be of much use. Geeks wanting to mess around with that can download here. Use @ your own risk.