Amaya XHTML chokes on URL ampersand delimiters

In pages to be parsed as XHTML, Amaya fails on URL's containing ampersand 
("&")
delimiters.

For example, <a href="http://a.b.org/c?d&e">URL with search string</a>

Amaya complains "not well-formed (invalid token)", after the token following 
the
first ampersand.

Without the XHTML DOCTYPE, this does not happen.

For a real-life example, see:
<a 
href="http://www.kindernetz.de/oli/tierlexikon/index.php?tid=115&reiter=steckbrief"> 
Eurasian Coot.</>