Originally Posted by tompe
I think that maybe the Perl module on cpan (was the name ebook or) might support it. There should be a thread about this module here.
No, the CPAN 'Ebook-tools' does not yet handle HuffDic compressed files, only standard compressed ones like MobiPerl. (Tommy, wouldn't it have been nice if the Perl code existed for that!
However, MobiHuff.py may do the trick. I have converted a ~ 10 MB .prc ebook this way and it worked well. Google for it and read this post
PM if you are interested and still need some assistance.