The Blue Book Of Guitars, referenced from Gibson's Website contains the entries:

SONGBIRD - square shoulder body similar to the Hummingbird & Dove Series, solid spruce top, mahogany back/sides/neck, morado fingerboard/bridge, gloss finished top with satin back. Available in Antique Walnut finish. New 1999. ----------------------
The Gibson catalog describes it as "Designed for the working musician who demands a superior sound at an affordable price. Antique Walnut Finish with glossy top and satin back and neck."
Here are their complete specs.

SONGBIRD DELUXE - similar to Songbird, except has Indian rosewood back/sides/fingerboard/bridge, abalone fingerboard inlays and rosette, includes active transducer pickup. Available in Antique Natural finish. New 1999.. ----------------------
The Gibson catalog describes it as "Superior performance model with rosewood back and sides and an active transducer pickup. Antique Natural Finish.."
Here are their complete specs.

Hope this helps,

      - Mark