Hi Stephen,
I can confirm that the injecting of chat messages from JavaScript using demo11.jsp to BigBlueButton is one-way.
We wrote this JavaScript API and the demo11.jsp example before the development of the BigBlueButton HTML5 client.
In the future, for two-way chat from JavaScript <-> BigBlueButton, the better approach would be to use the same mechanism as the BigBlueButton HTML5 client.
We've not made the HTML5 client modular (yet), where you could insert just chat, for example, in a web page, but it's something we'll look at during the development of the HTML5 client.
Right now, we're focused on finishing the development of the HTML5 client for a first release. See
Regards,... Fred