Ok, this one wasn't made with cels.  The 
characters are beautiful and the animation is 
stunning (IMO).  It's only about 13 episodes 
long and has special that was released after the 
series ended.

It's the story of a group of guys who are sort 
of a "spectral police" where they must 
investigate weird deaths in the living world.  
Each character has a dark story behind his 
involvement in this group...

As far as I know there isn't a US release (and I 
am unsure if one is slated...) but it is 
available via Chinese DVD release (subtitled in 
doable English) on eBay.

jINx