  We present an INTEGRAL data analysis of the X-ray transient \object{SAX
J2103.5+4545} during two outbursts detected in December 2002. The INTEGRAL
coordinates and error circle agree with the position of the recently proposed
optical counterpart. A power-law plus cut-off model provided a good fit to the
4-150 keV spectrum yielding a photon index of 1.0+-0.1, a cut-off energy
E_cut=7.6+-2.0 keV and a folding energy E_fold=30.9+-2.5 keV. The X-ray
luminosity in the 4-150 keV energy range was found to be 6.0x10^36 erg/s,
assuming a distance of 6.5 kpc. This luminosity, together with the derived
photon index, indicate that the source is in a bright state. A 354.9$+-0.5
second pulse period is measured. This value is significantly smaller than
previous measurements, indicating a long-term spin-up episode.
