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IIRC, ShadowStar mentioned amongst his many 3.5e answers that the Enervation spell wasn't changed, or at least it still didn't allow a Saving Throw. Dunno about Energy Drain. You might want to post your question on the ongoing 3.5 questions thread in General.
I dimly remember that I read something about saving throws and negative levels: you get a Fort save to avoid them altogether (and another to remove them without losing a level, if appropriate).