I know this is an old topic, but nevertheless I will give a answer that would help other people.
Of course, you can use ICN (IBM Content Navigator) instead of the old CGI / Servlet solution.
BUT, if you look at what the poster was giving for output:
...
<h3>Internet Connection Version 7.1.2.10.</h3>
<h4>The argument '_function' was not specified</h4><br>
<form>
...
Version 7.1.2.10 -> CMOD 8.3 Fix Pack 10.
Now if you look at the compatibility matrix between ODWEK and Server for CMOD, then you'll see that CMOD Server 9.0 cannot work with client/odwek prior to 8.5.
So my answer would have been:
A) You can use ICN, as proposed by all other posters
B) Please use ODWEK 9.0 and update your CGI with the one coming with ODWEK 9.0 and follow the installation of this component
CGI / Servlet are deprecate/obsolote, so it is advised to use another solution (read here ICN or custom code with Java API), but for current solution that cannot be changed like that, then you can still use the old CGI/SERVLET with of course the limitation of that obsolete solution.
Hope that helps,
Yours sincerely,
Alessandro