OK, I bit the bullet, removed the Delicious widget and replaced it with a plain-old RSS one. (Thanks to Andy Extance for trying it.) After a bit of CSS jiggery-pokery it almost looks the same as the original. For my RSS feed the URL is: http://feeds.delicious.com/v2/rss/adycoles. Replace the last bit with your Delicious username and you’re good-to-go.
However, I’m not satisfied and intend to pursue the loss of JSON feed (which the Delicious widget relies on).