Can't promise anything but would you try:

apt-get install ethtool

and add the following line to /etc/rc.local before the exit 0 statement:

ethtool -s eth0 wol g

And reboot. It's a fix that's worked for me in the past on some motherboards that wouldn't WOL properly.

Good luck

Oops, forgot to mention that you should confirm that the Ethernet port is really eth0. Since they migrated to 14.04.1 the (word that rhymes with dastards) have sometimes redefined it as p1p1, p32p1, etc. (there is a grub fix, but it's a PITA) and I'm now inspecting the ports to see where the Ethernet port actually is.

Just do an ifconfig to make sure it hadn't changed. If it did you'll have to change eth0 in the above example to whatever the heck it is now.