Oh another thing, I want to do the same for the "Recent Topics" hook (add rel="nofollow" to the user profile URLs), but have a similar issue..

I found the place I need to edit, but the URL in the hooksos_topicosrecentes is encoded like this:
Code: 
{IPSLib::makeProfileLink(IPSLib::makeNameFormatted( $r['topico']['starter_name'], $r['topico']['grupo1']), $r['topico']['starter_id'])}{parse template="user_popup" group="global" params="$r['topico']['starter_id'], $r['topico']['nome1']"}
is there a way to add rel="nofollow" to that?