Q: VPN server update actually did not solve my issue on 10.9.1 using Server 3.0.2

In my case I managed to fix it by means of this article:
http://jonsview.com/how-to-setup-os-x-10-9-as-a-l2tp-vpn-server-without-apples-s erver-app

And then especially the part about using an old version of Racoon (from Mountain Lion for example) to replace the current apparent defunct one in Mavericks...

By the way, note to others: it might have something to do with the fact that I had some silly trial version of VPN Activator (or something), which also ruined by settings it seems so I also deleted the /Library/Preferences/SystemConfiguration/com.apple.RemoteAccessServers.plist file and let it be recreated automatically again by the system.