Kubuntu Dapper pppd vs Win VPN

[Donn Ingle]

Hello all,
I have been away for a while, have moved house and my net connection
is really bad -- in fact that's what I'm hoping to get some help with
here.

I am being forced to use my Win laptop to connect to my new ISP by VPN.

On another list (glug-chat) I was given good info about
mtu and mpu that I set to 1400 and my woes went away ... for a while.

Windows (vpn) is doing something clever that Linux (at least Kubuntu
Dapper Drake) is somehow not doing (automatically) when it comes to
connecting to a server.

My WISP has been altering his network and since then things have
stopped working again. What he has done is move one antenna a little
such that from where I am, there is now a hop between me and his
server that answers the pppd call.

Windows works perfectly (I am on the laptop right now).
Linux just cannot connect to the server. The call to "pppd call qnect
nodetach" reports no useful messages or errors and just says "modem
disconnected" immediately.

Now, I have established (with help from glug) that this is likely not
the routing,
and I have those mtu setting in place in /etc/ppp/options, so I cannot
work out why Linux can't connect to that server. You can ping the
server and get a web-page (from its apache) from it, but cannot call
it from pppd.

Any ideas? What is Windows doing during a "vpn connection" that Linux is not?

I was advised to try 'ip route add 10.33.7.1/32 via 10.33.9.1' where
the last number is the address of the 'hop' between me and the server
(the first number). So far, I have not managed to connect.

Is there some way to get Kubuntu to 'detect' or 'sniff' the network so
that it figures out how to get to the VPN server the way Windows seems
to magically do it?

Thanks, hope someone can help.
/d