Well, I almost had it right the first time:

#!/usr/bin/perl -w
use strict;
use CGI::Pretty ":standard";

my $q= CGI->new();
print $q->table(
    { -border=>1, -cellpadding=>2, -cellspacing=>2 },
    Tr(
        { -align=>'LEFT', -valign=>'CENTER' },
        [
            $q->td( [ 'one', 1, 'I' ] ),
            $q->td(['one', '1', 'I']),
            $q->td(['two']) . $q->td({-colspan=>'2'}, ['2']),
            $q->td({-colspan=>'2'}, ['three', 'III']),
            $q->td({-colspank=>'3'}, ['four']),
        ]
    )
);
[download]

Thanks to jcwren for including fully functional code so I could test what I wrote.

        - tye (but my friends call me "Tye")