I solved it this way. sudo apt-get install kinit sudo apt-get install kio and the error disappeared. Bye. Matias W. Vera
*** Bug 379899 has been marked as a duplicate of this bug. ***
https://bugs.launchpad.net/ubuntu/+source/umbrello/+bug/1585611
This was really a downstream problem. Our upstreams is usually considered Qt and other libraries, even if this idea is a bit stretched. On the side, it is totally clear that we are the upstream for the distributions or packaging projects for various operating systems, which are then our downstreams. This bug capture a packaging issue (seen also on Debian, later solved) so I'm changing the resolution status of this bug accordingly.