iRony auth problem again

[Klaus Kuusela]

I've tried for hours to find out problem with iRony authentication. 
Installation is TBits/KolabScripts but addressbook is configured with 
active directory. Kolab-auth is still on background and uses local ldap. 
Environment CentOs7 / Kolab 3.4.

Error is this..

<d:error xmlns:d="DAV:" xmlns:s="http://sabredav.org/ns">
<s:sabredav-version>2.1.6</s:sabredav-version>
<s:exception>Sabre\DAV\Exception\NotAuthenticated</s:exception>
<s:message>No basic authentication headers were found</s:message>
</d:error>

$config['kolabdav_plugins'] is removed from dav.inc.php but could 
someone explain what auth backend is will use instead of own auth 
plugins or kolab_auth  ... and what auth lib I should offer for iRony to 
get this work again??

Bytheway.. is there somewhere xref service on Kolab package plugins / code ?