Dennis Masai, brother of Linet Masai (WXC champion) may be overage. Two articles I found state that he is 22 and 20, and the other says he is 17 last year, so 18 this year. What do you think?
Overage articles
Listed as 20 (article written in 2009)
http://www.bushdrums.com/news/index.php?shownews=2431
Listed as 22
http://www.iaaf.org/news/athletes/newsid=46494.html
Listed as 17