I have an issue with sending email from a Droid. It was working for the first few weeks and I can receive email messages, I just cannot send now. I have input the schools IMAP and SMTP settings correctly, so that does not seem to be the issue. The error message I get when trying to send mail is: 553 Blocked by RBL spamhaus.messagingarchitects.com . It happens on both 3G and WiFi connections. Has anyone seen this before? BB users are not getting the error message for the same configuration, so this seems like a Droid issue.