[Dovecot] IMAP proxy between Office 365 client/Sun Messaging Server

[John Dalbec]

I would like to be able to migrate messages from existing end-user 
accounts on Sun Messaging Server to Office 365 using an administrator 
login and password.  Unfortunately the migration tool for Office 365 
doesn't support SASL AUTHENTICATE PLAIN login.

The online documentation I've found suggests that I should be able to 
configure dovecot as an IMAP proxy and have it log in to Sun Messaging 
Server with AUTHENTICATE PLAIN and encode_base64("user\0admin\0adminpw") 
in response to a login from the Office 365 migration tool.  I'd like to 
configure dovecot to run only the IMAP proxy if possible.  I was 
thinking of setting all accounts to use the same (strong) password in 
the proxy.

Would anyone be willing to share a sample configuration?

Thanks,
John Dalbec
ellucian Luminis system administrator
Youngstown State University