Sometimes someone may want to link to your site using an indirect link, like a hit counting script where their link to you will be http://theirsite.com/out.php?id=x. If you want to allow this, emable the "reciprocated with" switch at Admin Panel -> Settings -> Switches. If you don't want to allow it, disable the switch.

When enabled, submitters will be able to type any URL and if that URL is found on their recipocal link page the reciprocation will be considered valid. You should thus check carefully that it redirects to your site before approving the link, or malicious submitters may use a URL that's on their page but doesn't link to you.