Who composed the National Hymn of Palestine. Not an Arab?

There’s plenty of evidence online that Arafat got Mikis Theodorakis to write A National Hymn of Palestine, when he visited Greece in 1981:

• The Jewish problem, according to Theodorakis
  (Haaretz interview, 2006)
• THEODORAKIS, A MAN OF PEACE (Theodorakis website)
• Μίκης Θεοδωράκης (Theodorakis website)
• PLO Commissions ‘national Anthem’ by Greek Composer (Jewish Telegraphic Agency, 1982)

It’s also quite clear that this anthem, which online evidence says had lyrics by Mahmoud Darwish and was presented in Algiers in 1988, is not the current national anthem of the Palestinian Authority.

Frustratingly, I can’t find any details online about what Mikis’ anthem was. But it’s neither Fida’i/Biladi, the current anthem, nor Mawtini, the old unofficial anthem.