nginx smtp proxy

[Scott Clark]

Hi There,

Is it possible to get the smtp proxy to make outbound connections on a
specific IP address?

Trying to use proxy_bind x.x.x.x but where ever I put it in the mail
config I get:

nginx: [emerg] "proxy_bind" directive is not allowed here

mail {
    # Pass any error message from the remote server
    proxy_pass_error_message on;
    server {
      listen     125;
      protocol   smtp;
      smtp_auth  none;
      auth_http  127.0.0.1:8008/auth-smtp.php;
      auth_http_header default-server 127.0.0.1;
      xclient   off;
    }
}

I don't see the proxy_bind directive listed in:
http://nginx.org/en/docs/mail/ngx_mail_core_module.html
http://nginx.org/en/docs/mail/ngx_mail_proxy_module.html
http://nginx.org/en/docs/mail/ngx_mail_smtp_module.html

Any ideas how to achieve this?

Thanks

Scott