No it was not a joke :)
I used stock phone for months, and few days ago I flashed this:
http://forum.xda-developers.com/xperia-z/general/android-5-1-available-yuga-pabx-t3054304
And now kernel is: 3.4.0-perf-gb5d5293-dirty
So my question now is, can I flash this CM 12.1 nightly from recovery...