How To Add: 'Download additional files:' To A Download?

[Dream]

How do you add the Additional downloads to a single page for example: http://www.tinyportal.net/index.php?action=tpmod;dl=item652 where it has the 'Download additional files:' link(s) below the download? Is this a mod? If so which one?

Thanks

[IchBin]

It is part of TP 1.0. Not available until its released, which we do not have a date for.