Hi,sorry for opening another thread, but I can't reply to a mail written by me. :-)
I fixed the tumblr issue. It was regarding mixed content if the wicket-site was accessed via https, so i used a protocol-relative url for the ajax call within the tumblr include.
If you access the page via https a https call is made to get the tumblr entries - if you access it via http a http call is made.
kind regards Tobias