Based on the popular manga (released by Viz in North America), Kekkaishi ran for 52 episodes a couple years ago in Japan.
 

 
Not sure who has licensed it yet, but Kekkaishi’s dub is currently in production in Los Angeles (maybe we will hear something at San Diego Comic-Con?)
 
Update- Based on some further information, I believe the license holder to be Viz or a company that we don’t traditionally think of as an anime company, but that isn’t confirmed (officially OR unofficially.)