[exim] exim delivering via lmtp (tcp/ip) , how to ??

Hello,

I try to make lmtp authentication over tcp/ip to a cyrus-imap server
for my test I configured lmtpd with '-a' option to not use authentication.

but now , I need to use plain authentication

I have an saslauthd daemon which connect to an ldap db

I haven't found the way to make it work, can someone help me to do this ?

thank you very much for your help

Patrice