I got it working thanks to you, fanoush.

And with your last message you hit it on the nail again, since the culprit was with the chap secrets (a typo).

Now, I'm trying to do the routing.

I put a script file with route commands in /etc/ppp/ip-up.d/
but it doesn't appear to run though.

I wonder if anyone is using /etc/ppp/ip-up.d/ scripts succesfully on IT 0S2007?