I discovered a bug in your Wordpress plugin with another plugin - Inline Editor. Inline Editor allows you to edit a posting with a rich test menubar without having to go to the admin pages.
URL for he plugi n-
I'm fairly sure that the bug is only with your plugin because I am testing a configuration and I have a number of plugins in the mix. I went through a debug process of deactivating most of the plugins until Inline Editor worked and then reactivating them one
or two at a time until it stopped working.
I hope you have time to fix this because I like your plugin using it wold be part of evangelizing micro formats.