msdb database mail taking longer than 5 minutes

Hi Guys,

I am using SQL server 2008R2 instance which is monitored by red-gate SQL monitor. Database mail process is taking more than 5 minutes to execute. It always come up in my long running query list.

Below is the sql fragment. I have no idea how to make it execute faster and where to tune it. Any direction will be much appreciated.

Process ID: 79
Process name:   DatabaseMail - DatabaseMail - Id<8708>
Database:   msdb
Host:   SQL2K8R2
User:   MyUser
Process login time: 5 Oct 2011 5:03 PM
Query start time:   5 Oct 2011 5:03 PM
Query duration: 585 sec
SQL process fragment
-- sp_readrequest : Reads a request from the the queue and returns its
-- contents.
CREATE PROCEDURE sp_readrequest
@receive_timeout INT -- the max time this read will wait for new message
AS
BEGIN
SET NOCOUNT ON

-- Table to store message information.
DECLARE @msgs TABLE
(
[conversation_handle] uniqueidentifier,
[service_contract_name] nvarchar(256),
[message_type_name] nvarchar(256),
[message_body] varbinary(max)
)

-- Declare variables to store row values fetched from the cursor
DECLARE 
@exit INT,
@idoc INT,