  We calculate the coefficients of operators with dimensions d <= 7 in the
operator product expansion of correlators of q Gamma Q currents, for the
effective field theory of an infinite-mass quark, Q. Exact two-loop results are
obtained, with an arbitrary gauge group and spacetime dimension, for the
perturbative (d=0) and quark-condensate (d=3) contributions, confirming our
previous result for the anomalous dimension of the current. Leading-order
results are given for light-quark operators with d=5, 6, 7 and gluon operators
with d=4, 6. The existence of a perturbative correction of order 100% precludes
a reliable determination of f_B from non-relativistic sum rules.
