I am using version 8.8 of this plugin with WP 3.5.1.
When people enter their email address into the widget or subscription page and click either "subscribe" or "unsubscribe," they get the message, "This is somewhat embarrassing, isn’t it? It seems we can’t find what you’re looking for. Perhaps searching can help." It won't let them do either function.
Any help is greatly appreciated as we have a large number of subscribers. This function hasn't worked in a couple of versions, and we keep getting emails from people wanting to subscribe.