not able to send mail [Connection timed out]

[ggpanta]

Hi, I am not able to send email from my mail server.
Its on a public IP no NAT, all proper ports are open in the firewall.
hosts file is correct as is the DNS record's
I used various tools to check the DNS records and everything works propertly.

I do receive mail correctly but am not able to send email.
DNS lookups are enabled both on the server and in global and I am not using a relay.

checking /var/log/mail I can see that all outgoing mail timeouts .
zimbra is on openSuSE 10.1 and Zimbra is verison 4.02.

Thanks in advance.