Thanks! I have it!
It was not easy at all to find any spanish dictionary that uses DICT protocol You are using, and changing the code to something else without knowing python would be crazy as well. Finally the easiest way was to find the dictionary
http://sercari.esdebian.org/33720/di...stellano-libre and install dictd locally.
After that the only thing I had to do was to change dict.org to localhost in file
/usr/lib/calibre/calibre/gui2/viewer/dictionary.py
The only thing that does not work is Control+L shortcut..
Thanks for the hints!