When you apply for a job as a professor, and your field is in a foreign language, DO NOT have your letters of recommendation sent in languages other than the official language of instruction of the university. A letter in German, Italian, Arabic, Farsi, Rumanian, or Greek isn't going to help you, at all. I'm a professor of Spanish and all my letters were in English. If I were applying to a school in Spain, I'd ask people to write letters in Spanish, or provide certified translations. It seems pretentious, and not everyone on search committees might speak the language. Some colleges make it a regular practice to invite people from outside the Department to sit on search committees. If your recommender cannot write in another language, by all means, pay someone to do a certified confidential translation.
Also, if you've earned a degree from a foreign university, such as a Diplome de etudes profundises, provide a local equivalent. While I know that the degree means "Diploma of deep studies," I don't know how that translates into the American academic system. I could go and look it up, but when I have 80 applications times 20 pages to read, I don't want to have to take the time. Help your committee out.
If it's a teaching college, don't start your letter with, "In my dissertation..." I cannot stress enough the need to tailor your letter to each institution. Know your audience. Look and see what kinds of classes are being and have been offered recently in your field. K N O W your audience.
Be smart; keep it simple. ¡Buena suerte! (trans. "Good luck!")