smtpclient - custom x-receiver tag

Hi

I have a requirements to send an email to person with custom x-receiver header. So, We have compliance system which will capture the emails based on x-receiver.

When ever I am sending email with TO and From, smtpclient automatically adds x-receiver header with To address. Since I am getting

X-Sender: John@dummyco.com
X-Receiver: John@Doe.com    << How to Remove this?
X-Receiver: ccc@custom.com
MIME-Version: 1.0
From: John@dummyco.com
To: John@Doe.com
Date: 4 Feb 2014 16:39:45 -0500
Subject: test email

Thanks

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