[ns] Where can i get the implementation source code of DBTMA protocol running in ns2?

[mhxin]

Hi,everybody:
 i want to run some simulations, the MAC protocol is DBTMA.
 But i couldn't find the implementation source code of this protocol in the 
Internet.
 who can tell me where can i get it?
 thanks a lot for your help!

My email is: [EMAIL PROTECTED]
                           HongLiang Ma from BeiJing
                                         2006.08.14