Top panel: spectral region around the Lyα feature with our best fit to the red wing overplotted in red. The model consists of a fully ionised intergalactic medium and a column density in the GRB host of log N_{H i} = 19.91 ± 0.02. The 1σ noise is plotted as a dotted line. Bottom panel: residuals from the fit, with the ± 1σ region marked with a dotted line. The skyline residual in the bottom of the Lyα line should not be interpreted as Lyα emission.