The authors are grateful to J. Chapront for providing the NFA code and H. Varvoglis for a critical reading of the first draft of this paper. Also, we would like to thank A. Milani for his critical remarks on the role of secular resonances which improved the presentation of our work. E. Pilat-Lohinger and K. Tsiganis gratefully acknowledge financial support received by the Jubiläumsfonds - Projektnummer 6446 `Trojanerbahnen' of the Oesterreichische Nationalbank . K. Tsiganis would like to thank all the people in the Institut für Astronomie for their hospitality during his stay in Vienna. The work of K.Tsiganis was partially funded by the State Scholarships Foundation of Greece (IKY) .
© European Southern Observatory (ESO) 2000
Online publication: February 25, 2000