If you refer to the ability of the media player to understand the DIVX fourcc code, I got this "hint" from this:

http://maemo.org/community/wiki/VideoEncoding/

Also trying different fourcc (e.g. MP4V), I had no success. The output of the encoding is not a DIVX though, it is encoded using the MPEG-4 codec, that is supported by the builtin mediaplayer.