Accessing debug registers with nasm

From: Devesh Agrawal (spamtrap_at_crayne.org)
Date: 10/30/04 

Date: Sat, 30 Oct 2004 16:53:25 +0000 (UTC)

Hi ,
I want to know how I can access debug registers in intel 386 , like
DR6 , DR7 etc using nasm , when i say something like xor dr6,dr6 , it
tells that I have used invalid operands , any ideas ?
Sincerely
Devesh Agrawal.