The participants as well as the song remain a mystery, but Billboard.com said recording has been taking place at Conway Studios.
Jackson spokesman Raymone Baine said the pop star rewrote the song, originally announced as "From the Bottom of My Heart," and the new name as well as new theme will be announced in coming days.
Baine also said Jackson cut down the number of celebrities he originally planned to participate in the single, but he refused to name them as well.
Jackson, who is living in Bahrain and recently went to London to work on the track, is participating in the Los Angeles recording via satellite and telephone.
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