[sudo-discuss] mailing list help

Hey there! Inés Chapela here with a problem regarding mailing list managing..I work for the Greenhorns (check us out: www.thegreenhorns.net) Anyway, we're trying to send out an e-blast to promote our latest project, Up UP Farm Film Festival, which is a series of indie films and shorts that explore the questions facing the new farmers movement. We primarily use mailchimp for this type of thing and for some reason they are saying we have "stale" emails and are threatening to delete our e list unless we hire a third party company to clean up our list. I'd love to just leave mailchimp and get another mailing list company that doesn't cause so much trouble...Anybody have advice for a good route to take here? Any help greatly appreciated. Inés