I have the exact same problem.
Interesting thing is that with a “theme” like “connections” or “pool” – the sidebar with all my bloglinks work, no problem But with the “WordPress Default 1.6 by Michael Heilemann” or the “K2 0.95 RC1” I get the same error message as stated above…
Any help is highly appreciated!
(by the by my page, in Swedish, is https://www.goldkette.se)