Using ppp/tun0 manually, how to trigger 'pf' automaticaly

[O. Hartmann]

Hello.

I use the ppp utility to configure and setup a line (at the moment no 
other way possible). How can I trigger 'pfctl -F all -f /etc/pf.conf'
after the line has been setup to make pf working with the tun0 assigned IP?

Or are there other way doing so?

Thanks,
Oliver