Version 2.3 is available upstream. Please consider updating! It seems that version 2.3 is available upstream, while the latest version in the Gentoo tree is 1.52-r2. You think this warning is false? Read more about it here.
Natural Docs is an open-source, extensible, multi-language
documentation generator. It extracts specially formatted comments
from source code and builds HTML documentation from it. The syntax
is transparent so that the comments in the source code read just as
easily as the generated documentation. It also focuses on automation
and high-quality generated output.