2.2.4.2 (stable):

* Namespace sigc is now documented, in order to make large chunks of the
  reference reappear.  (Daniel Elstner)
* The shipped reference documentation has been regenerated using Doxygen
  1.6.1, so that the document type is now XHTML 1.0.  (Daniel Elstner)
* The shipped Devhelp file has been generated with a newer version of the
  XSLT script in mm-common, so that documentation groups no longer appear
  as namespace prefixes in the keyword list.  (Daniel Elstner)