Yes it seems that the Digg REST API is changed without a notification. I opened an issue here[1], and we will fix it.
[1] http://code.google.com/p/mashups4jsf/issues/detail?id=32
--Hazem Ahmed Saleh Ahmed
Author of (The Definitive Guide to Apache MyFaces and Facelets):
http://www.amazon.com/Definitive-Guide-Apache-MyFaces-Facelets/dp/1590597370
http://www.amazon.com/-/e/B002M052KY
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