SMTP authentication through telnet

[paresh@pareshlinux ~]$ perl -MMIME::Base64 -e 'print encode_base64("Username")'
cWxjX3NhbWVlcg==
[paresh@pareshlinux ~]$ perl -MMIME::Base64 -e 'print encode_base64("Password")'
c2FtZWVy
[paresh@pareshlinux ~]$ telnet 10.10.10.13 25
Trying 121.241.242.215...
Connected to mail1.mailserve.net (10.10.10.13).
Escape character is '^]'.
220 host.mailserve.com ESMTP Postfix
ehlo 121.241.242.215
250-host.mailserve.com
250-PIPELINING
250-SIZE 15728640
250-VRFY
250-ETRN
250-AUTH LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
AUTH LOGIN
334 VXNlcm5hbWU6
cWxjX3NhbWVlcg==
334 UGFzc3dvcmQ6
c2FtZWVy
235 2.7.0 Authentication successful