Which language should I learn to be more hireable in Japan: Spanish or Chinese?

Question:

Let me start this question off by telling you my current position. I work for a Japanese automotive parts manufacturer in the U.S. I translate of design specs and interpret for meetings. I have Japanese Language qualifications and interpreter training, so please don't answer this question with "Japanese"

In addition to that, I have conversational ability in Spanish and Chinese. I would like to start working on improving one of these languages. Which one would make me more hireable as a translator? I have seen a lot of postings for Chinese-Japanese-English positions so I am leaning toward this. Any thoughts from people who are over there?

Answer:

um.., I'm confused.
I had a feeling that you're teaching Japanese from the following question (which had no respond from you..)
http://ca.answers.yahoo.com/question/ind…
日系企業にお勤めで、企業内日本語研修という意味だったのでしょうか？
教材についての相談は会社にすべきだったのでは？

To answer your question, my honest opinion is, "to start working on improving one of Chinese/Spanish languages” means you're still not ready to be a translator for these language. There're more Cantonese people living outside of China, as you might know. Do you read Chinese (both Mandarin and Cantonese) sentences? If you go for "Chinese-Japanese-English positions" professionally, you need to be already fluent(-level) in all these languages.
----------------
今、追記を読みました。 日本語本当にお上手だと思います。( I usually do
proofreading here in "Japan" So just one thing: 獲得→ 習得 ^^;)

数年前、カナダで日本語の上手な中国籍の夫婦と知り合ったのですが、ご主人は
日本に10年滞在歴があるという方でした。 無口な方でしたが、日本語力は相当
おありのようで、日本では特許事務所に勤めていらっしゃったそうです。 今は
アメリカの法律事務所で、やはり日本企業対象（だったか… 要するに、中国語と
日本語力を必要とする）の特許関連の職務に携わっていらっしゃるそうです。
What I want to say is, in my humble opinion, while you become multilingual,
you might need a specific field you should be proud of. For example, as you
currently work for automotive parts manufacturer, you'd better stay in the
same field, which will bring higher-quality experiences.
Translators are also required their "得意分野"

私も、スペイン語より中国語の方が今後は需要も高いと思います。

どうぞ頑張ってください。

---------- Spanish option
"司法（法廷）通訳人　court interpreter"
should be widely demanded as more and more South Americans (except for Brazilians) live in Japan, especially in the industrial district. If you're interested in, target will be "gaining technical terms" (I heard this when I was in Japan)
¡Buena suerte!