openssl s_client -starttls smtp uses the hardcoded EHLO
"openssl.client.net". 

Advanced spamfilters check EHLO hostnames against
blacklists and may reject these sessions since "client.net" is an
existing parked domain and blacklisted on jp.surbl.org.


Client:
#openssl s_client -connect <munged>:25 -starttls smtp -crlf
CONNECTED(00000003)
didn't found starttls in server response, try anyway...
140655663449768:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown 
protocol:s23_clnt.c:683:
---
no peer certificate available
---
No client certificate CA names sent
---
SSL handshake has read 177 bytes and written 246 bytes
---
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
---

NOTE: error message reports: "didn't found starttls". Bad grammar, should 
probably read: "didn't find starttls"

MTA log output:
Nov 24 09:43:23 <munged> postfix/smtpd[7623]: NOQUEUE: milter-reject: EHLO from 
unknown[<munged>]: 550 5.7.1 black listed URL host openssl.client.net by 
<munged>; proto=SMTP helo=<openssl.client.net>


Possible fixes:
 - make the EHLO hostname configurable (preferred)
 - use the client hostname (which could in turn be rejected because it is often 
not fully qualified)
 - use a hostname in the openssl.org domain or one of 
example.com/example.org/example.net (which could also be rejected since the 
target server may detect that the client does not belong to these domains)


Additional Information:
openssl version
OpenSSL 1.0.0e 6 Sep 2011

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