Hi,
the sender verification does not use TLS encrypted connections to verify
senders:
550-Verification failed for <cyborg2@???>
550-Called: 83.246.80.130
550-Sent: RCPT TO:<cyborg2@???>
550-Response: 550 Receiver does not accept unencrypted connections
550 Sender verify failed
Solution: switch to TLS encrypted connections.
Marius