I guess it is one of those words that came from Latin... According to this data base "Derived from the Basque place name Etxabier meaning "the new house". I don't know why it is that the old Spanish "X" became "J" or why the old Spanish "F" became "H". Another good example of this "phenomenum" is
Ximun and
Ximena, as they are more comonly spelled Simón and
Jimena, now days.
I would say it is 100% Spanish, since it is Basque and the Basque country is in Spain
But hey, what do I know ;op?
Magia.