Integrate TextSecure protocol into SMS messaging in Ubuntu phone

As many of you will know, the TextSecure protocol has been integrated into CyanogenMod:

http://www.cyanogenmod.org/blog/whisperpush-secure-messaging-integration
https://whispersystems.org/blog/cyanogen-integration/
http://www.forbes.com/sites/andygreenberg/2013/12/09/ten-million-more-android-users-text-messages-will-soon-be-encrypted-by-default/

They have done this at a middleware level, meaning that any app using the normal Android SMS APIs to send an SMS/MMS to another TextSecure/CyanogenMod user will automatically gain end-to-end encryption over a federated data channel (Cyanogenmod runs its own servers for its users, but they communicate with TextSecure's).

The protocol and code all appear to be open source and is widely considered to be the current state of the art in secure messaging, with application-level forward secrecy and advanced ratcheting. Unlike Telegram, all messages on TextSecure (not just "secret chats") are end-to-end encrypted.

It would be excellent to see this implemented in Ubuntu Phones. In addition to interoperating with TextSecure, Signal and Cyanogenmod users, it would also mean that Ubuntu-to-Ubuntu text messages would be secure by default (and over the data channel, so in many countries, free or cheaper).

People could, of course, continue to install additional apps like Telegram on their Ubuntu phones and these would work as normal, but it would add a layer of security to anything that would otherwise be sent as a txt/MMS message.

Other posts/questions discussing this idea:
https://lists.launchpad.net/ubuntu-phone/msg09724.html
http://support.whispersystems.org/customer/portal/questions/11385434-textsecure-on-ubuntu-phone