[pptp-server] Kernel oops with 2.4.18 + mppe -- patch included

[Thorvald Natvig]

Mar 23rd [pptp-server] Kernel-2.4.18-0.4 and PPTP Problem.
Mar 14th [pptp-server] Kernel panic with 2.4.17-2.4.19pre2 + Win98
client

So it seems I'm not the only one with the problem. In the Mar 14th post,
Nate Carlson has tracked the problem down to Win98 and 98SE clients, so
it may well be that if you only connect with the "newer" microsoft OSes
this won't be a problem.

With the patch, the problem goes away, and I've now successfully
transferred multiple GB to and from most of the MS OSes.

.. On a sidenote, I have also ported and finetuned the pppd.authexec
patch for 2.4.1 if anyone is interrested. On our setup here, we use that
together with prehashed passwords to have a large and somewhat secure
userdatabase... More secure than plaintext passowords anyway ;)

> Odd. My distro has standardized on 2.4.17 for a while now and 
> not had this problem. Perhaps its unique to 2.4.18.