[Seaside] error when testing the Seaside Tutorial

[Rob Withers]

I am following: 
http://www.hpi.uni-potsdam.de/hirschfeld/seaside/tutorial?_k=sYMMWLGI&_s=NLtXszDVFNfYkdvO

I loaded the changeset into a seaside image where the WAKom was running.  I 
pointer my browser to http://localhost:8080/seaside/todo/.

I got an error in my server: UndefinedObject>>doesNotUnderstand: #default

from this method:

WARenderPhaseContinuation>>updateRoot: anHtmlRoot
	anHtmlRoot meta contentType: self application contentType.
	anHtmlRoot meta contentScriptType: WAMimeType textJavascript.
	anHtmlRoot htmlAttributes
		at: 'xmlns' put: 'http://www.w3.org/1999/xhtml';
		at: 'xml:lang' put: 'en';
		at: 'lang' put: 'en'.
	anHtmlRoot beXhtml10Strict.
	anHtmlRoot title: 'Seaside'.
	self application libraries
		do: [ :each | each default updateRoot: anHtmlRoot ].
	self session updateRoot: anHtmlRoot

What should I do to fix this?

Many thanks,
Rob