iRony not working with Centos 7/Kolab 3.5 Development

[Carpenter, Troy]

Kolab 3.5/Development on Centos 7.

I tried to configure OutlookDAV to work with Kolab, but it doesn't seem 
to authenticate properly.

Output from httpraw:

[05-Oct-2015 19:46:52,830700 -0400]: RESPONSE: 401 Unauthorized
a: application/xml; charset=utf-8

<?xml version="1.0" encoding="utf-8"?>
<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>

If I point OutlookDAV to my 3.4 installation on Centos 6.7, it works 
fine.

Is there something missing in the development repository?

I noticed in dav.config.inc this was missing compared to 3.4:

// Roundcube plugins. Not all are supported here.
$config['kolabdav_plugins'] = array('kolab_auth');

but putting it in didn't help.