updated 11:28 pm EST, Thu December 19, 2013
Small patch allows client, server to be under different NAT providers
Apple's latest update to OS X 10.9 Mavericks Server has fixed a virtual private network (VPN) connectivity issue. The update fixes issues preventing clients from communicating with OS X VPN services through the L2TP protocol when the client and server were under different NAT gateways.
The update is a standalone package, and requires both OS X Mavericks client 10.9.1 and Server 3.0.1 to be installed and running. The update weighs in at 1.6MB, and is available through Apple Support Downloads.