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We present the first high-resolution (6.2 to 7.7 km/s FWHM) spectra of theAPM BR J0307-4945 quasar at z_em = 4.73 obtained with UVES on the 8.2m VLTKueyen telescope. We focus our analysis on a damped Ly-alpha (DLA) system atz_abs = 4.466 with a neutral hydrogen column density N(HI) = (4.68 +/- 0.97)10^{20} cm^{-2}. It is the most distant DLA system known to the present date,observed when the age of the universe was only 1.3 Gyr. It shows complex low-and high-ionization line profiles spanning ~240 and 300 km/s in velocity spacerespectively. We derive accurate abundances for N, O, Al, Si and Fe, and placea lower limit on C and an upper limit on Ni: [N/H] = -3.07 +/- 0.15, [O/H] =-1.63 +/- 0.19, [Al/H] = -1.79 +/- 0.11, [Si/H] = -1.54 +/- 0.11, [Fe/H] =-1.97 +/- 0.19, [C/H] > -1.63 and [Ni/H] < -2.35. The derived high metallicity,1/90 solar, shows that this very young absorber (< 1.3 Gyr) has alreadyexperienced a significant metal enrichment. The [O/Si] ratio is nearly solarsuggesting a limited amount of dust, the relative [Si,O/Fe] abundance ratiosshow a similar enhancement as observed in the Milky Way stars with comparablemetallicities, and the [N/O] ratio is very low. All these results point to anenrichment pattern dominated by Type II supernovae which suggests a Milky Waytype evolutionary model.Comment: 11 pages, 5 figures, Accepted for publication in A&

UVES observations of a damped Lyαsystem at $\mathsf{{\vec z}_{abs} = 4.466}$ towards the quasar APM BR J0307-4945