Ubuntu Servers :: Offering MS-CHAPv2 In Pppd Causes Windows Error 778

I previously had an Openswan-based IPsec/L2TP solution that was working marvelously on Ubuntu 8.04 LTS. I upgraded to Ubuntu 10.04 LTS and cannot seem to get it working again.

First, Ubuntu's version of Openswan (2.6.23) does not work with NATted transport mode [1]. Since an L2TP connection is in transport mode, I downloaded Openswan 2.6.27 to /usr/src/, and ran "make programs" and "make install".

This allowed my IPsec and xl2tpd configuration that I previously had to work again like they were supposed to. (Aren't you relieved this isn't an IPsec question?)

Anyway, xl2tpd starts up an instance of pppd for the new incoming connection using /etc/ppp/options.xl2tpd. But for some reason my previous configuration was not working. After hours of searching and tracking things down, I've narrowed it down to the following lines in my options.xl2tpd file:

Code:
require-mschap-v2
plugin winbind.so
ntlm_auth-helper '/usr/bin/ntlm_auth --helper-protocol=ntlm-server-1 --require-membership-of="EXAMPLEDOM\VPN Users"'

[Code].....