ACS OAuth2 tokens

Hi,

I have created Service Bus with ACS, attached WCF relay service and everything work great.
Now I would like to use OAuth2 with my relay service.

In first step I sent POST to get token from :
https://mynamespace.accesscontrol.windows.net/v2/OAuth2-13

with success

{
  "token_type": "http://schemas.xmlsoap.org/ws/2009/11/swt-token-profile-1.0", 
   "access_token": "net.windows.servicebus.action=Listen......", 
   "expires_in": "10800", 
   "scope": "http://{mynamespace}.servicebus.windows.net/"
}
Now
I need some example how to set headers with this token.
When I set headers with something like this

Authorization: Bearer "net.windows.servicebus.action=Listen..."

I have
"Invalid authorization header: The request is missing WRAP authorization credentials"

Why WRAP? I would like to use OAuth2 not OAuth WRAP