Body viewer replaces non UTF8 characters with ???

[johnsimons]

Gives a message with eg:

<?xml version="1.0"?>
<AnotherMessage xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.net/">
  <OrderId>456</OrderId>
  <Data>مرحبا بالعالم</Data>
</AnotherMessage>

The result displayed in the body viewer is:

<?xml version="1.0"?>
<AnotherMessage xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.net/">
  <OrderId>456</OrderId>
  <Data>????? ???????</Data>
</AnotherMessage>