If a test file contain a package "main", the Distributed test will fail.
For example, the code below in the test file.


    ...

    package NoForkProcess;
    use vars qw( @ISA );
    @ISA = qw( TAP::Parser::Iterator::Worker );

    sub _use_open3 { return }

    package main;

    my $listener = IO::Socket::INET->new(
	Listen => 5,
	Proto  => 'tcp'
    );

    ...
