Hi, Olivier was sure reading your mails. ;)
Although we could nor reproduce this problem with our current installation neither find any clue in the CPAN modules changelogs, we did some changes that should do the trick.
You will find a patch here : http://sourcesup.cru.fr/viewvc/viewvc/branches/sympa-5.2-branch/src/List.pm?root=sympa&r1=4244&r2=4377 Please let us know if this solves your problem or not. Regards, -- David Verdin Comité réseau des universités