Recent work on this text calls into doubt that there was a Hebrew original behind the Greek and Latin. I agree that it was probably composed in Greek. A good case has also been made that it is a Christian composition. See M. de Jonge and M. Tromp, The Life of Adam and Even and Related Literature (Guides to Apocrypha and Pseudepigrapha: Sheffield, 1997) and the relevant essays in M. de Jonge, Pseudepigrapha of the Old Testament as Part of Christian Literature: The Case of the Testaments of the Twelve Patriarchas and the Greek Life of Adam and Eve (SVTP 18; Leiden: Brill, 2003).
UPDATE: For previous posts in Phil's ongoing series on the Old Testament Pseudepigrapha, start here and follow the links.
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