managesieve problem

Hi,

i am struggeling with a managesieve problem, we are using docker mailserver and managesieve login does not work, if i understand correctly, then dovecot should offer something like this

"SASL" "PLAIN"

on our server it is simply empty

"SASL" ""

i was trying to authenticate in a telnet connection

AUTHENTICATE "PLAIN" "LOGINSTRING_HERE"

And i get this

NO "Error in MANAGESIEVE command received by server."

first of all i would like to ask where the SASL capabilites come from, how can i get it to offer "PLAIN" or "AUTH"

everything else (e.g. sieve itself) just works find

Cheers Soeren