The order of the pppoe rc script is wrong, relative to other rc scripts.
# chkconfig: 2345 80 20
For example, ntpd has
# chkconfig: - 26 74
ntpd will be started before pppoe and will fail. Basically pppoe should
start before ALL other services which depend on a live Internet
It's fixed in rp-ppoe-3.0-3. You will find it in the rawhide.