broken markup due to error-reporting strangles XML-parsing (e.g. in chat-module)

Set up a virgin moodle.
Create a Course.
Add Chat.
Login as user without any rights for that Chat.
Try to access.
You should get an error: "Sorry, but you do not currently have permissions to do that (Talk in a chat)"
What you see is the browser complaining about invalid tag-folding in

</div> <!-- end div content -->
--^

Have a look at the delivered markup: the error breaks conntent-delivery just inside a tables cell. Don't know how to solve that, but why would the chat-module force XML-output via <xml... declaration? Could that be surpressed if any error-printing is predictable?

Apreciate Your work,

greetz,

Christopher