Postfix not sending mail

[amarumayo]

Hi all,

I am attempting to send mail with postfix. The mails are not coming through. When I tail my mail log I get this error when the email attempt is made but I don't really know what it means. Is anyone able to assist me?

Feb 28 19:58:42 bird postfix/pickup[25141]: 8C49E8006C2: uid=33 from=<www-data>
Feb 28 19:58:42 bird postfix/cleanup[26115]: 8C49E8006C2: message-id=<20130301005842.8C49E8006C2@bird>
Feb 28 19:58:42 bird postfix/qmgr[25142]: 8C49E8006C2: from=<www-data@bird>, size=468, nrcpt=1 (queue active)
Feb 28 19:58:42 bird postfix/error[26117]: 8C49E8006C2: to=<amarumayo@gmail.com>, relay=none, delay=0.23, delays=0.15/0/0/0.08, dsn=4.4.1, status=deferred (delivery temporarily suspended: connect to alt2.gmail-smtp-in.l.google.com[2a00:1450:4013:c00::1b]:25: Network is unreachable)

Thanks in advance,
Chris

[mockturtl]

Feb 28 19:58:42 bird postfix/error[26117]: 8C49E8006C2: to=<amarumayo@gmail.com>, relay=none, delay=0.23, delays=0.15/0/0/0.08, dsn=4.4.1, status=deferred (delivery temporarily suspended: connect to alt2.gmail-smtp-in.l.google.com[2a00:1450:4013:c00::1b]:25: Network is unreachable)

Firewall, or IPv6 problem.

https://encrypted.google.com/search?q=p ... nreachable