How to Encrypt Querystring (Server.Transfer)

Hi,
I am developing a module which will be use to encrypt the query string, so the users will not see the actual data passed to the pages. And I have managed to this by using the IHttpModule. And this works fine, as far as the page is called using Response.Redirect method. But this fails when the page is called using the Server.Transfer method, since the HttpContext.Current.Response object will return null. So how can I achieve this. How to encrypt the query string when the page is called using Server.Transfer method


Thanks in advance
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