Redirect to external Web page while posting hidden field and without using ?

 I see variations on this theme in the forums, but nothing that quite answers my specific need.
How can I duplicate the following <form> functionality in ASP.NET without using <form> (and no javascript!!!)?:
<body onload="document.forms[0].submit()">
<BODY>
<form action="http://www.someotherwebsite.com/theirpage.aspx"
method="POST">
<input type="hidden" name="refid" value="hiddenvalue"> </form> </BODY>
 So what I'm asking is how can I make my page automatically redirect to an external Web site page and post hidden data to that external page at the same time?
I've seen examples that come close with HttpWebRequest, but none that redirect to that external page WHILE posting the hidden data.
Thanks,
--Will

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