I assumed he was talking about perlunit (sourceforge), which, if you squint you will notice
mentions Test::Unit, which I believe is essentially
the same as CPAN Test::Unit, which is
no longer being actively developed because, as you say,
the standard Perl testing framework, prove, Test::More,
Test::Class and all the other fine Test:: modules on CPAN, that work nicely with the standard Perl testing framework,
but do not work with Test::Unit, are so much better.
Update: In addition to the standard Perl documentation Test::More, prove etc., the excellent Perl Testing: A Developer's notebook has plenty of examples to get you started with Perl testing.