I have a reverse DNS and SPF records correctly setup for my mail server. Sending webmail from it works perfect.
The problem is when Thunderbird sends out emails, it is using the client's IP address for the hostname. I have SMTP authentication and specified my mail server's as the outgoing SMTP. Mail is being sent, but it is not "signing" the email with the mail server's IP address.. it is using the client's.
Is there any way to fix this?
This is the spam error I get when sending from Thunderbird:
Spam: Reverse DNS Lookup, SPF_SoftFail