I have repeated this in Firefox and Safari on two separate installs of Wiccle.

If you click on the Mail function (one of the many) and "Compose" a message and send it, and then click on Quote, there are two places on the form that produce [[text]], as per the screnshot below.

Same thing goes for if you receive a message and click on the quote button.  Basically, every time I used that Quote button, it produced this with [[CRECEIVER]] and [[CCANCEL]].

Yes, this happens if you click Quote on the mail that you see below the editor in the preview panel. Tagged as bug, fixed for next build.

To fix this, open /core/ajax/message.php at line #286:

        $mail = Utility::array_stripslashes($mail);

Add after:

        $mail['mail_id'] = !empty($mail['mail_id']) ? $mail['mail_id'] : mt_rand();

This will give the mail shown in the AJAX area a proper identifier, fixing the parsing issue (resulting from defective Quote/Reply buttons missing an ID).