The attached patch set introduces L2TP support for Linux. There are 2 
patches.

ppp-add-pppol2tp-plugin.patch
Adds a pppol2tp plugin which lets pppd use the Linux pppol2tp.ko kernel 
driver to pass PPP frames in L2TP tunnels using PPPoL2TP sockets.

ppp-add-openl2tp-plugin.patch
Adds an event interface which is used by the OpenL2TP implementation to 
receive events from pppd using a Unix socket.

These plugins are being actively used by users of OpenL2TP and other
L2TP daemons. Please consider for inclusion in the next release of
pppd.

Thanks!

-- 
James Chapman
Katalix Systems Ltd
http://www.katalix.com
Catalysts for your Embedded Linux software development