5.6 ifconfig doesn't init my point-to-point-devices (SLIP/PPP) right

Try setting the remote IP-address as the very last argument at the ifconfig-command. If you want this to run from `/etc/netstart'/`/etc/hostname.*', please note the options' order given in `/etc/netstart' and fix your `/etc/netstart', if necessary (see section 3.5.1 `/etc/netstart').