How to enable opportunistic locking in OS X Server 10.10

We have Windows clients with a software which relies on opportunistic locking using SMB2. I would like to get rid of the Windows Server and use OS X Server File Sharing for this.

With OS X Server 10.6 this was possible: http://support.apple.com/kb/PH8462

But I cannot find instructions for Yosemite 10.10 file sharing.