There are many reasons why a site would go in supplemental, for example the use of the word "teen" which is a word google doesn't like, or the amount of the increase of outgoing/incoming links per scan, or a certain frequently used keyword. Like this there are over a dozen more reasons or there is just isn't a reason.
http://www.google.com/search?hl=en&l...com+dream8teen
http://www.google.com/search?hl=en&l...com+surfcuties
As you can see they both have pages in "supplemental". But the domains don't seem to be in "supplemental".
I would recommend to get some more incoming links, but not outgoing links. So get some sites/blogs to link to you but don't link back.