Strange problem on lmtp with dovecot 2.3.2.1

[davide marchi]

Hi to all i have compiled and installed dovecot 2.3.2.1 on debian 6 with
success but now i'm facing a strange problem on communication from postfix
installed on server A with dovecot installed on server B (which version is
2.3.2.1). All incoming emails delivered from esternal from server A to
server B with LMTP is rejected with this message error

"smtpgw postfix/lmtp[1772]: 6194CA00B3: to=<xxxxxxxxxxxx at mail.cgilfe.it>,
relay=192.168.10.50[192.168.10.50]:24, delay=0.02, delays=0/0.01/0.01/0,
dsn=5.5.4, status=undeliverable (host 192.168.10.50[192.168.10.50] said:
501 5.5.4 Invalid FROM: Missing domain (in reply to MAIL FROM command))"

I cant identify what is the problem , for now i have bypassed lmtp using
smtp but my goal is returning to lmtp that i have used since old versions
of dovecot.
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