A timeout certainly sounds like a firewall problem.
I'm not familiar with linode. Maybe you can open the firewall?
Thanks Jason - I'll have the Sys Admin take a look and update post.
I've had two other support questions for Linode, but neither of them had the timeout problem you are having.
Thanks Jason! The system administrator should let me know soon if the Firewall is blocking outgoing mail. Will update post when we have more info - stay tuned.