HI Bhaskar,
I am not sure if the business process you are following is correct. Business wise - I don't think it is. I think you have to clear a vendor account to GL account (accounts payable) and then clear the customer to another GL account (accounts receivable). On an accounting standpoint, what you are doing is not a good practice when you clear vendor again a customer directly. I am not 100% on this but I think you should check with the accountants of your business/client if this is what they really want to do.
Josef