  In the framework of the ERTBP, we study an example of the influence of
secondary resonances over the long term stability of Trojan motions. By the
integration of ensembles of orbits, we find various types of chaotic diffusion,
slow and fast. We show that the distribution of escape times is bi-modular,
corresponding to two populations of short and long escape times. The objects
with long escape times produce a power-law tail in the distribution.
