RECEIVE Statement Not Working

I followed an example using the AdventureWorks database to set up a simple messaging test on one database:




Code Block
-- We will use adventure works as the sample database
USE AdventureWorks
GO
-- First, we need to create a message type. Note that our message type is
-- very simple and allowed any type of content
CREATE MESSAGE TYPE JobRequest
VALIDATION = NONE
GO
-- Once the message type has been created, we need to create a contract
-- that specifies who can send what types of messages
CREATE CONTRACT JobRequestor
(JobRequest SENT BY INITIATOR)
GO
-- The communication is between two endpoints. Thus, we need two queues to
-- hold messages
CREATE QUEUE RequestorQueue
CREATE QUEUE ReceiverQueue
GO
-- Create the required services and bind them to be above created queues
CREATE SERVICE Requestor
ON QUEUE RequestorQueue
CREATE SERVICE Receiver
ON QUEUE ReceiverQueue (JobRequestor)
GO
-- At this point, we can begin the conversation between the two services by
-- sending messages
DECLARE @conversationHandle UNIQUEIDENTIFIER
DECLARE @message NVARCHAR(100)
BEGIN
BEGIN TRANSACTION;
BEGIN DIALOG @conversationHandle
FROM SERVICE Requestor
TO SERVICE 'Receiver'
ON CONTRACT JobRequestor
WITH ENCRYPTION=OFF, LIFETIME= 600;
-- Send a message on the conversation
SET @message = N'Hello, World';
SEND ON CONVERSATION @conversationHandle
MESSAGE TYPE JobRequest (@message)
COMMIT TRANSACTION
END
GO
-- Receive a message from the queue
RECEIVE CONVERT(NVARCHAR(max), message_body) AS message
FROM ReceiverQueue
-- Cleanup
DROP SERVICE Sender
DROP SERVICE Receiver
DROP QUEUE SenderQueue
DROP QUEUE ReceiverQueue
DROP CONTRACT HelloContract
DROP MESSAGE TYPE HelloMessage
GO


This all works fine but if I run the section that creates the message and then copy the RECEIVE section to a new query window and execute it, nothing is returned. If I run the RECEIVE section within the same query window it returns the 'Hello World' message as expected. I am new to Service Broker and so am assuming that I am missing something obvious!!