  An energy $E=\omega J$ is derived for gravitational spin-orbit coupling by
frame-dragging $\omega$ acting on angular momentum $J$. This interaction
defines a no-boundary mechanism for linear acceleration of magnetized matter
along the axis of rotation of black holes. We explain GRB030329/SN2003dh by
centered nucleation of a high-mass black hole with rapid rotation, producing
baryon-poor ejecta by gravitational spin-orbit coupling. The duration of the
burst is attributed to spin-down in the emission of gravitational-waves by a
surrounding non-axisymmetric torus.
