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The scattering lengths of a two pion system are the {\it golden magnitudes}to test the QCD predictions in the low energy sector. The DIRAC (PS-212)experiment at CERN will obtain a particular combination of the S-wave isospin 0and 2 scattering lengths by measuring the lifetime of pionium, thehydrogen-like $\pi^+ \pi^-$ atom. This measurement tests the accuratepredictions of the Chiral Perturbation Theory. The most recent experimentalresults are presented.Comment: Talk presented at Xth International Conference on Hadron Spectroscopy  HADRON '03, August 31 -- September 6, 2003, Aschaffenburg, German

The pion-pion scattering lengths from DIRAC