Change SMTP Auth method

[dgt...@gmail.com]

Hey Guys, 

We're having problems sending Mails via SMTP TLS. We are getting the message Authentication failed when ever we try. 

We found out that the SMTP Server replies different Auth methods:
'250-AUTH CRAM-MD5 PLAIN LOGIN DIGEST-MD5 NTLM\r\n'

And then the engine chooses CRAM-MD5 all the time, what seems to be default. 

Resulting in: '535 5.7.0 Authentication failed\r\n'

We have a installation on a customer server where it works using the office365 smtp service. 

That replies: 
'250-AUTH LOGIN XOAUTH2\r\n' 

Then the engine (telnet) uses AUTH LOGIN ... 
and we are getting: 
'235 2.7.0  Authentication successful\r\n'

So, is there a way to tell the engine to use AUTH LOGIN instead of CRAM-MD5 ? 


Greetings 
Daniel