Email into SPAM

[Mirco]

The admin of the email server, told me that the problem is that the LM introduces himself as localhost, this is the problem:

from=<***> to=<***>
proto=ESMTP helo=<localhost>
Nov 26 14:37:33 smtpservice1 postfix/cleanup[23052]: AAD0E255: message-id=<>
Nov 26 14:37:33 smtpservice1 opendkim[22852]: AAD0E255: can't determine
message sender; accepting


Is there a way to change the "helo" paramiter that the LM write?

Thanks