We describe 4-dimensional complex projective manifolds X admitting a simple normal crossing divisor of the form A+B among their hyperplane sections, both components A and B having sectional genus zero. Let L be the hyperplane bundle. Up to exchanging the two components,(X, L, A, B)is one of the following: 1)(X,L)is A scroll over P~1 with A itself a scroll and B a fibre, 2)(X,L)=(P~2×P~2, δ_P~2×P~2(1,1)) With A∈│δ_P~2×P~2(1,0), B∈│δ_P~2×P~2(0,1), 3)X=P_p~2(γ)whereγ=δ_p~2(1)~+~2+δ_p~2(2), L is the tautological line bundle, A=P_P~2(δ_P~2(1)~+2), and B∈π~*│δ_P~2(2)│, where π: X→P~2 is the scroll projection. This supplements a recent result of Chandler, Howard, And Sommese.
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