  We present spectroscopic and photometric observations of the eclipsing binary
V32 located in the central field of the globular cluster NGC 6397. The variable
is a single-line spectroscopic binary with an orbital period of 9.8783d and a
large eccentricity of e=0.32. Its systemic velocity (gamma=20.7 km/s) and
metallicity ([Fe/H] -1.9) are both consistent with cluster membership. The
primary component of the binary is located at the top of the main-sequence
turn-off on the cluster color-magnitude diagram. Only a shallow primary eclipse
is observed in the light curve. Based on stellar models for an age of 12Gyr and
the mass-function derived from the radial velocity curve, we estimate the
masses to be M_p=0.79 Msun and M_s=0.23 Msun. The light curve of V32 can be
reproduced by adopting R_p=1.569 Rsun and R_s=0.236 Rsun for the radii and
i=85.44 deg for the system inclination. The system geometry precludes
observations of the secondary eclipse. The large eccentricity of the orbit is
puzzling given that for metal poor, halo binaries the transition from circular
to eccentric orbit occurs at an orbital period of about 20 days. We suppose
that the orbit of V32 was modified relatively recently by dynamical interaction
with other cluster star(s).An alternative explanation of the observed
eccentricity calls for the presence of a third body in the system.
