Like its authors, Ncat isn't perfect. But you can help make
it better by sending bug reports or even writing patches. If Ncat
doesn't behave the way you expect, first upgrade to the latest
version available from https://nmap.org. If the problem persists,
do some research to determine whether it has already been
discovered and addressed. Try Googling the error message or
browsing the nmap-dev archives at http://seclists.org/.
Read this full manual page as
well. If nothing comes of this, mail a bug report to
<email@example.com>. Please include everything
you have learned about the problem, as well as what version of
Ncat you are running and what operating system version it is
running on. Problem reports and Ncat usage questions sent to
firstname.lastname@example.org are far more likely to be answered than
those sent to Fyodor directly.
Code patches to fix bugs are even better than bug reports.
Basic instructions for creating patch files with your changes are
available at https://svn.nmap.org/nmap/HACKING. Patches may
be sent to nmap-dev (recommended) or to Fyodor directly.