Conversion to 7BIT required but not supported

[Damian]

>> What kind of software is that on 127.0.0.1:10025? It's neither amavis nor postfix.
> 
> Crap I missed that! it's James Java SMTP for Ciphermail.

If you cannot enable 8BITMIME support on it, you might try to discard
the 8BITMIME ehlo keyword on the 10021 amavis instance/policybank. This
way, your postfix:25 should convert to 7BIT before feeding the mail into
amavis:10021. This is also mentioned in [1] with its caveats.

[1] https://www.ijs.si/software/amavisd/amavisd-new-docs.html