Originally Posted by Profits of Doom

Gmail has become a mother fucker in blocking emails from IP's with porn domains. I used this trick a while back, not sure if it still works but you can give it a try. Send out several emails a day to Gmail test accounts. Go into the spam folder and click the "Not Spam" tab on each email. After you pass a certain threshold of mails marked not spam from different accounts Gmail will start inboxing the emails. Note that this only worked on non spammed IP's (which you already said they weren't) that were only getting flagged due to porn domains...