lib/ropenstack/identity/v2.rb
def scope_token(para1, para2 = nil, para3 = nil)
                  if ( para2.nil? )
                          data = { "auth" => { "tenantName" => para1, "token" => { "id" => token() } } }
                          @data = post_request(address("/tokens"), data, token())
                  else 
                          authenticate(para1, para2, token(), para3)			
                  end
          end
def scope_token(para1, para2 = nil, para3 = nil)
                  if ( para2.nil? )
                          data = { "auth" => { "tenantName" => para1, "token" => { "id" => token() } } }
                          @data = post_request(address("/tokens"), data, token())
                  else 
                          authenticate(para1, para2, token(), para3)			
                  end
          end
Scope token provides two ways to call it:
 	scope_token(tenantName) => Just using the current token and a tenantName it
 				   scopes in the token. Token stays the same.
	scope_token(username, password, tenantName) => This uses the username and
				   password to reauthenticate with a tenant. The
				   token changes.