[Zope-dev] Best way to email a newsletter to thousands of recipients from a Zope site Zope site

Hi, I need to add a newsletter feature to a Zope site. Interested people will be able to register their email addresses, and the newsletter will be mailed to all addresses every 1-2 weeks. The number of recipients could potentially have 4 zeroes in it (and no, it won't be 0000). What would be the best way to do the mailing? Use mailhost with a very long recipient list? Call mailhost once for every recipient? Use some external tool to do the mailing? Thanks in advance Itai Tavor -- Itai Tavor -- "Je sautille, donc je suis." -- itavor@vic.bigpond.net.au -- - Kermit the Frog -- -- "What he needs now is understanding... and a confederate victory" -- -- Dr. Jacobi, Twin Peaks --