or download this
>> 220 ooa Microsoft ESMTP MAIL Service, Version: 5.0.2195.5329 ready
+at Wed, 21 May 2003 14:11:18 -0600
<< ehlo CZXXPRA01SV0007
...
>> 250 2.1.0 jenda@krynicky.cz....Sender OK
<< rcpt to: <jenda@krynicky.cz>
>> 550 5.7.1 Unable to relay for jenda@krynicky.cz