I hope this report is not too late.
In the last 3 months, I implemented XEP-0136 for Prosody. This experience is really awesome: great mentor(Matthew Wild), active communities(Prosody, Gajim) and the wonderful organization(XSF), they've helped me a lot on this project. Many thanks to them! And, thanks to Google, who makes all of these possible, :)
What have been done
XEP-0136 is almost completely implemented:
The 3rd part of XEP-0136, Off The Record, is too complicated, and not practical I think. So MattJ and I decided not to implement this feature, and implement another "XEP" instead -- XEP-xxxx: Message Archive Management, which is a much simpler version of XEP-0136.
What to be done
I'll continue maintaining mod_archive and mod_archive_muc. There are still some little issues, and I'll fix them in the future.
All the code is available at prosody-modules. Any suggestions are welcome. :) Please report issues here, or contact me at shinysky1986 (A T) gmail dot com.