Thanks for reporting this issue. I found a similar bug report in Debian and have attached a bug watch. Looks like the Debian maintainer have started to look into packaging the latest version.
** Bug watch added: Debian Bug tracker #731634 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731634 ** Also affects: xz-utils (Debian) via http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=731634 Importance: Unknown Status: Unknown ** Tags added: upgrade-software-version -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to xz-utils in Ubuntu. https://bugs.launchpad.net/bugs/1440417 Title: Old package, please move to stable 5.2 Status in xz-utils package in Ubuntu: New Status in xz-utils package in Debian: Unknown Bug description: http://tukaani.org/xz/ Already released 5.2 stable version with threading support, it can much improve performance for end user To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xz-utils/+bug/1440417/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp