In this archived message; Peter explains here how to get ip address for various gmail servers - which can then be added to whitelist...
http://marc.info/?l=openbsd-misc&m=136449396910976&w=2 When I try this process for yahoo.com; I get $ host -ttxt yahoo.com yahoo.com descriptive text "v=spf1 redirect=_spf.mail.yahoo.com" $ host -ttxt _spf.mail.yahoo.com _spf.mail.yahoo.com descriptive text "v=spf1 ptr:yahoo.com ptr:yahoo.net ?all" What should I do with "ptr" info?
