  Iron emission lines at 6.4-6.97 keV, identified with fluorescent Kalpha
transitions, are among the strongest discrete features in the X-ray band. These
are therefore one of the most powerful probes to infer the properties of the
plasma in the innermost part of the accretion disc around a compact object. In
this paper we present a recent XMM observation of the X-ray burster 4U 1705-44,
where we clearly detect a relativistically smeared iron line at about 6.7 keV,
testifying with high statistical significance that the line profile is
distorted by high velocity motion in the accretion disc. As expected from disc
reflection models, we also find a significant absorption edge at about 8.3 keV;
this feature appears to be smeared, and is compatible with being produced in
the same region where the iron line is produced. From the line profile we
derive the physical parameters of the inner accretion disc with large
precision. The line is identified with the Kalpha transition of highly ionised
iron, Fe XXV, the inner disc radius is Rin = (14 \pm 2) R_g (where R_g is the
Gravitational radius, GM/c^2), the emissivity dependence from the disc radius
is r^{-2.27 \pm 0.08}, the inclination angle with respect to the line of sight
is i = (39 \pm 1) degrees. Finally, the XMM spectrum shows evidences of other
low-energy emission lines, which again appear broad and their profiles are
compatible with being produced in the same region where the iron line is
produced.
