Since there has been all the dicussion regarding ST -v- GRT, here's an multi-level GRT version. Runs about twice as fast.

print for map{ 
    substr( $_, 1+index( $_, '|' ) )
} sort map {
    my $key1 = $_;
    map { 
        pack 'NA* NA* A1 A*', 
            split( '\.', $key1 ), 
            split( '\.', $_ ), 
            '|', 
            $hash{ $key1 }{ $_ }
    } keys %{ $hash{ $_ } };
} keys %hash;
[download]

Just plug it into the test script above to see it run.