Is this really patent-free LZW?

[Don Marti <dmarti@zgp.org>]

This web site claims to use something called the Adaptive Tree
Algorithm to create LZW-compressed GIFs without using any
patented algorithms.

http://www.danbbs.dk/~dino/whirlgif/gifencod.html

Source for gifencode.c is on the page.

Is this for real?

-- 
Don Marti               |  Use GIF images?  You may already be a
dmarti@zgp.org          |  criminal.
http://zgp.org/~dmarti  |  
whois DM683             |  http://burnallgifs.org/