Hello everybody!

I have some problems sending mails from my linux box MTA because some recipients are rejecting my mails due to a IP spam rule (I have an IP which range is cataloged as a dynamic ISP IP... and this is not true because I'm paying for a fix IP address).

Anyway, the point is that I have decided to relay all my outbound messages throw smtp.gmail.com (I have created an account and I have add an alias with my own domain also).

I have follow this how to on the wiki:

The error appears when I try to send and email. I received a response from postfix saying:
This is the Postfix program at host zzz.yyyy.xxx.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

The Postfix program

<xxx@xxx.xx>: host gmail-smtp.l.google.com[] said:
530 5.7.0 Must issue a STARTTLS command first j8sm4520902gvb.14 (in reply
to MAIL FROM command)
Dec 28 10:01:15 servidor amavis[3298]: (03298-01) Passed CLEAN, LOCAL [] [] <example@example.com> -> <xxx@xxx.xx>, Mes
sage-ID: <6041582.01198832369222.JavaMail.root@servidor.exa mple.com>, mail_id: UVrKmZCyEWfv, Hits: -3.239, 84905 ms
Dec 28 10:01:15 servidor postfix/smtp[32549]: 6F8F86E094B: to=<xxx@xxx.xx>, relay=[], delay=90, status=sent (250 2.6.0 Ok, i
d=03298-01, from MTA([]:10025): 250 Ok: queued as 9B3EE6E094C)
Dec 28 10:01:15 servidor postfix/qmgr[30457]: 6F8F86E094B: removed
Dec 28 10:01:16 servidor amavis[3298]: (03298-01) extra modules loaded: Net/LDAP/Bind.pm
Dec 28 10:01:16 servidor postfix/smtp[813]: 9B3EE6E094C: to=<xxx@xxx.xx>, relay=gmail-smtp.l.google.com[], delay=5, status=bounc
ed (host gmail-smtp.l.google.com[] said: 530 5.7.0 Must issue a STARTTLS command first j8sm4520902gvb.14 (in reply to MAIL FROM command))
Dec 28 10:01:16 servidor postfix/cleanup[32548]: B12196E094B: message-id=<20071228090116.B12196E094B@servidor.example.co m>
Dec 28 10:01:16 servidor postfix/qmgr[30457]: B12196E094B: from=<>, size=3147, nrcpt=1 (queue active)
Dec 28 10:01:16 servidor postfix/qmgr[30457]: 9B3EE6E094C: removed
Dec 28 10:01:20 servidor postfix/lmtp[833]: B12196E094B: to=<example@example.com>, relay=servidor.example.com[], delay=4, status=sent (250 2.1.
5 OK)
Someone has get involved in the same situation? I will really appreciate any help on this topic because I have all my mail server stooped and nobody can send mails :S

Thanks for all!