  Aims. We study the geometry and kinematics of the circumstellar environment
of the Be star Kappa CMa in the Br gamma emission line and its nearby
continuum. Methods. We use the VLTI/AMBER instrument operating in the K band
which provides a spatial resolution of about 6 mas with a spectral resolution
of 1500 to study the kinematics within the disk and to infer its rotation law.
In order to obtain more kinematical constraints we also use an high spectral
resolution Pa beta line profile obtain in December 2005 at the Observatorio do
Pico do Dios, Brazil and we compile V/R line profile variations and spectral
energy distribution data points from the literature. Results. Using
differential visibilities and differential phases across the Br gamma line we
detect an asymmetry in the disk. Moreover, we found that kappa CMa seems
difficult to fit within the classical scenario for Be stars, illustrated
recently by alpha Arae observations, i.e. a fast rotating B star close to its
breakup velocity surrounded by a Keplerian circumstellar disk with an enhanced
polar wind. Finally we discuss the possibility for kappa CMa to be a critical
rotator with a Keplerian rotating disk and try to see if the detected asymmetry
can be interpreted within the "one-armed" viscous disk framework.
