Does anyone develop diffserv model in ns?

[wuwei <wuwei@mail.cic.tsinghua.edu.cn>]

ns-users

I am studying diffserv and I wonder wheather someone develop code to implement diffserv 
in ns? 
If no, could anyone give me any sugestion on implementing it?
If yes,Do you mind share your code?
 
Thanks in advance!
           
wuwei