I managed to preauth a user via SOAP by following Preauth - Zimbra :: Wiki
However, there are instruction to preauth for admin tasks via REST but there is nothing about doing the same via SOAP ; any hints ?

Is it even possible or am I have to use REST ? the Auth method from zimbraAdmin does not have a preauth mechanism in the referenced doc.

PS: It seems to me a bit unclear which URL and namespace should be used for SOAP preauth requests.