Siebel Thin/Think clients getting hanged while processing inbound message using Response groups

Hi,

I have to handle/process the Inbound email message. For this I have created Response group to handle/process the Inbound message(as attached). I am able to read and process it successfully by using 'eMail Response - Process Message' workflow (made few customizations according to our req.) which is invoked by Workflow Process Manager in response group(see screenshot)

The problem here is - Siebel Thin/Think clients are getting hanged when the Inbound message is being processed. (I think its due to synchronous request). Not able to do anything in Siebel Client till the Inbound message is processed.