An epoxy-imide adhesive has been exposed to tensile creep at various elevated temperatures in air. Using viscoelastic techniques, the glass-transition temperature has been monitored both for the polymer having undergone creep and the material simply aged at the same temperature. Defining Delta T-g as the T-g of the loaded material minus that of the aged material, for conditions otherwise equivalent, unusual behaviour has been observed. Initially, Delta T-g increases for short times but later decreases and becomes slightly negative. This behaviour has been attributed to two phenomena, occurring concomitantly : that of macromolecular chain orientation causing a reduction of free volume and a (relative) increase of T-g, and chain scission caused both by chain elongation and thermal degradation, leading to a drop of T-g. A simple model is proposed to explain semi-quantitatively the observed behaviour.