Hi, I am getting this error whenever I send mail externally. I can route mail to my own domains normally.

tail /var/log/mail

Oct 2 01:46:14 phoivos-VMail zmtomcatmgr[11822]: status OK
Oct 2 01:47:30 phoivos-VMail postfix/qmgr[1705]: 3A8DE21C6D: from=<sender@mydomain.gr>, size=11348, nrcpt=1 (queue active)
Oct 2 01:47:30 phoivos-VMail postfix/qmgr[1705]: 51EB521D57: from=<sender@mydomain.gr>, size=5592, nrcpt=1 (queue active)
Oct 2 01:48:01 phoivos-VMail postfix/smtp[11906]: connect to q0.netfirms.com[64.34.66.70]: Connection timed out (port 25)
Oct 2 01:48:01 phoivos-VMail postfix/smtp[11905]: connect to q0.netfirms.com[64.34.66.70]: Connection timed out (port 25)
Oct 2 01:48:12 phoivos-VMail zmtomcatmgr[12062]: status requested
Oct 2 01:48:12 phoivos-VMail zmtomcatmgr[12062]: status OK
Oct 2 01:48:31 phoivos-VMail postfix/smtp[11906]: connect to q1.netfirms.com[64.34.66.80]: Connection timed out (port 25)
Oct 2 01:48:31 phoivos-VMail postfix/smtp[11905]: connect to q1.netfirms.com[64.34.66.80]: Connection timed out (port 25)
Oct 2 01:48:31 phoivos-VMail postfix/smtp[11905]: 3A8DE21C6D: to=<recipient@hisdomain.com>, relay=none, delay=1823, status=deferred (connect to q1.netfirms.com[64.34.66.80]: Connection timed out)
Oct 2 01:48:31 phoivos-VMail postfix/smtp[11906]: 51EB521D57: to=<recipient@hisdomain.com>, relay=none, delay=1823, status=deferred (connect to q1.netfirms.com[64.34.66.80]: Connection timed out)
Oct 2 01:50:33 phoivos-VMail zmtomcatmgr[12350]: status requested
Oct 2 01:50:33 phoivos-VMail zmtomcatmgr[12350]: status OK

These are substituting the correct mail addresses.
sender@mydomain.gr, recipient@hisdomain.com

I can ping or telnet to port 25 on the recipients mail server and the same in reverse. also the LMTP port is open in the firewall. I also have DNS resolves enabled on zimbra.

Thanks in advance.