I was struggling with the same thing and have tried your code. I am getting strange results: sometimes I am getting encouraging codes back such as 250 ("ok") and 354 ("go ahead") but often I get 502 ("unimplemented (#5.5.1)"). There seems to be no pattern in a series of 10 emails sent out through the same connection - codes seem random and some of the email is delivered, while most is not. Any ideas? thanks. (See below for the Debug output result after sending 2 messages -both undelivered)

Net::SMTP: Net::SMTP(2.13) Net::SMTP: Net::Cmd(2.12) Net::SMTP: Export
+er(5.562) Net::SMTP: IO::Socket::INET(1.25) Net::SMTP: IO::Socket(1.2
+6) Net::SMTP: IO::Handle(1.21) Net::SMTP=GLOB(0x104834)<<< 220 www.my
+isp.com 
ESMTP Net::SMTP=GLOB(0x104834)>>> EHLO www2.myisp.net 
Net::SMTP=GLOB(0x104834)<<< 250-www.myisp.com 
Net::SMTP=GLOB(0x104834)<<< 250-PIPELINING 
Net::SMTP=GLOB(0x104834)<<< 250 8BITMIME 
Net::SMTP=GLOB(0x104834)>>> AUTH LOGIN 
Net::SMTP=GLOB(0x104834)>>> ZGVsZWdhXzE= 
Net::SMTP=GLOB(0x104834)>>> am93b2JvMTI= 
Net::SMTP=GLOB(0x104834)>>> MAIL FROM: 
Net::SMTP=GLOB(0x104834)<<< 502 unimplemented (#5.5.1) 
Net::SMTP=GLOB(0x104834)>>> RCPT TO: 
Net::SMTP=GLOB(0x104834)<<< 354 go ahead 
Net::SMTP=GLOB(0x104834)>>> DATA 
Net::SMTP=GLOB(0x104834)<<< 250 ok 1019918963 qp 4227 
Net::SMTP=GLOB(0x104834)>>> To: myself@hotmail.com 
Net::SMTP=GLOB(0x104834)>>> From: theprogram@mydomain.com
Net::SMTP=GLOB(0x104834)>>> Subject: first test
Net::SMTP=GLOB(0x104834)>>> 
Net::SMTP=GLOB(0x104834)>>> testing...
Net::SMTP=GLOB(0x104834)>>> . 
Net::SMTP=GLOB(0x104834)<<< 502 unimplemented (#5.5.1) 
Net::SMTP=GLOB(0x104834)>>> AUTH LOGIN 
Net::SMTP=GLOB(0x104834)>>> ZGVsZMdhXzE= 
Net::SMTP=GLOB(0x104834)>>> am93b3JvMTI= 
Net::SMTP=GLOB(0x104834)>>> MAIL FROM: 
Net::SMTP=GLOB(0x104834)<<< 502 unimplemented (#5.5.1) 
Net::SMTP=GLOB(0x104834)>>> RCPT TO: 
Net::SMTP=GLOB(0x104834)<<< 502 unimplemented (#5.5.1) 
Net::SMTP=GLOB(0x104834)>>> DATA 
Net::SMTP=GLOB(0x104834)<<< 502 unimplemented (#5.5.1) 
Net::SMTP=GLOB(0x104834)>>> To: myself@hotmail.com 
Net::SMTP=GLOB(0x104834)>>> From: theprogram@mydomain.com
Net::SMTP=GLOB(0x104834)>>> Subject: second test
Net::SMTP=GLOB(0x104834)>>> 
Net::SMTP=GLOB(0x104834)>>> Hi, this is another test
Net::SMTP=GLOB(0x104834)>>> . 
Net::SMTP=GLOB(0x104834)<<< 250 ok 
Net::SMTP=GLOB(0x104834)>>> QUIT 
Net::SMTP=GLOB(0x104834)<<< 250 ok
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