Persistant ethernet names and ppp

Hi,

I'm running Gentoo, and have now got persistant ethernet names..

This has created a problem, I'm not sure where it starts, but I
dont have those names in /dev, as in /dev/enp4s1 (which is the port that plugs in the ADSL)

from the man page, if I leave out the slash "/" it appends the
/dev/ itself, but enp4s1 doesn't exist in /dev, so, how can I get pppoe working :(

if I do ifconfig -a I get the interface showing, I can set a IP,
but I cannot get pppoe :(