two listeners with different "driver = " configs

[mj]

Hi,

I would like to have two seperate imap listeners, with different 
authentication settings, but the mailstore and userbase etc will be 
identical.

I know I can do this:

service imap-login {
   inet_listener imap {
     port = 143
   }
   inet_listener imap2 {
     port = 144
   }
}

But I'm unsure how to configure imap/143 with "driver = ldap" and 
imap2/144 with "driver = pam"

Just to explain why i would like this:

I am using pam-script-saml (https://github.com/ck-ws/pam-script-saml) to 
enable saml-based access to dovecot. I would like to have one listener 
144 to only serve this saml authentication listener, and the regular 143 
listener with driver = ldap.

Is that config possible?

Best regards,
MJ