This bug was reported to MKDoc-dev on 17 March 2005.
This page: http://www.helpisathand.gov.uk/news/technology/2004/nov/phone-cast/
Has one HTML component with this as the first line:
<h4>Friday, 5<sup>th</sup> November 2004</h4>
And there is also a link component:
Address (URI): http://www.three.co.uk/ Title: 3 Description: External link to the 3 website.
But, and this is really weird because the first lines doesn't have the number 3 in it, the generated page has this, invalid, XHTML:
<h4>Friday, 5<sup>th&(<a href="http://www.three.co.uk/" class="mkdoc-link" title="External link to the 3 website.">3</a>) November 2004</sup></h4>