Weird email sending rejection from on-rev using Sarah's library

[George C Brackett]

I'm using Sarah Reichelt's SMTP library, which has worked well for me  
for many years (thanks, Sarah!).  I'm now asking it to send mail via  
one of my on-rev email addresses (I use on-rev to host my  
luceatlux.com domain):
	Email address gbrackett at luceatlux.com
	Username: (correct - Apple mail uses the same one)
	SMTP server: mail.luceatlux.com with Authentication checked
	Password (correct - Apple mail uses the same one)

Using Sarah's latest stack, downloaded today, and attempting to send a  
single email titled "Test" with message "This is a test of Sarah's  
current library." I get an alert "Connection error: NotAuthenticated"  
with the following log:

220-odin.on-rev.com ESMTP Exim 4.69 #1 Wed, 09 Sep 2009 14:28:03 -0500
-> EHLO 172.16.1.7
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
-> QUIT
250-odin.on-rev.com Hello pool-96-233-30-16.bstnma.east.verizon.net  
[96.233.30.16]
250-SIZE 52428800
250-PIPELINING
250-AUTH PLAIN LOGIN
250-STARTTLS
250 HELP
->

Any ideas why this might happen?  As I say, Apple mail has no  
difficulty with these parameters. Maybe there's a hint in the log?   
Why does it mention bulk mail?

George