Message Queues

Hi

I was experiencing an issue yesterday where I had over 900 messages in the queue. I had to filter and delete only A31 messages out of the queue allowing the rest of them to be processed.  I tried to use SQL to set the status of the message to 'Suspended' however the A31 messages still remained on the queue and I had to suspend manually by going through each message.  Is there a way of Suspending or Aborting only certain type of messages in a queue.  I started with a SQL statement even though the status gets updated to suspended the message remains in the queue tab, how do I remove the message from the queue?  Thank you for your help.

update 
Ens.MessageHeader
Set Status ='Suspended' WHERE ID =(
SELECT
Ens.MessageHeader.ID
FROM Ens.MessageHeader inner join EnsLib_HL7.Message

on EnsLib_HL7.Message.ID=
Ens.MessageHeader.MessageBodyId 
WHERE 
Ens.MessageHeader.TargetConfigName ='Operation_Name' and 
EnsLib_HL7.Message.name ='ADT_A31' and Ens.MessageHeader.Status='Queued')

Kind Regards,

Salma