is ethX is up?
see ifconfig, see if ethX is up, otherwise even if pppd is actived, u still won't see internet.
dunno what program you are running for your dsl dail up, i'm using roaring pengis,
it comes with adsl-stop, adsl-start, adsl-setup, adsl-connect
i have to bring ethernet up first before dail up, or else won't work.
from your error msg, doesn't look like your pppd is setup correctly.