InfoPath Dev

I followed the discussion here and changed my data source xsd file to convince Infopath that my field is XHTML and not a string. I can then bind it to a rich text box, but I see all the html markup as text in the box.  I tried adding the  namespace to the root element, but it makes no difference. 

My data source is simply returning this:

<div xmlns="http://www.w3.org/1999/xhtml"> <b>Bold</b> </div>  

What am I missing?

I got this working by having a rich text box bound to an HTML field in the main data source by using this code on form load:

string s = DataSources["REST Web Service"].CreateNavigator().SelectSingleNode("/ns1:ArrayOfRisk/ns1:Risk/ns1:Details", NamespaceManager).Value;
MainDataSource.CreateNavigator().SelectSingleNode("/my:myFields/my:field1", NamespaceManager).AppendChild(s);

But it is annoying having to have a redundant field in my main data source. If anyone knows a better way, I'd be most grateful.

Thanks