I've embedded a link in one of my postings on www.jimandellie.com. The link was www.openenglish.com. When I display HTML it looks fine; however, when clicking the link it goes to an error page - here. Why is the prefix of my site showing up? Is this a bug or possibly related to a plug-in I have ...

For some reason when I try to configure and manage plug-ins on the Serendipity website I only see 21 available. I read there are over 100 or 200. Any thoughts?