Tenon today announced that Post.Office, its mail server for Mac OS X, now features list serving capabilities. Post.Office 3.5.3 can handle hundreds of mailing lists with thousands of subscribers. Pricing for Post.Office follows a sliding scale, with a starter package available for US$295 that supports 100 mailboxes and 10 mailing lists. A free version is available that supports 10 mailboxes and two mailing lists.