You may need to enable proxy-arp on the lan-interfaces. Check this explanation: http://forum.mikrotik.com/t/is-it-possible-to-communicate-pppoe-to-an-ipv4-network-when-they-are-in-the-same-subnet/86450/1
You may need to enable proxy-arp on the lan-interfaces. Check this explanation: http://forum.mikrotik.com/t/is-it-possible-to-communicate-pppoe-to-an-ipv4-network-when-they-are-in-the-same-subnet/86450/1