Hi,
i did a small test lab.

WAN ---- CISCO7200VXR (OSPF)---- ROUTERBOARD 1 (OSPF)----- ROUTERBOARD 2 (OSPF)

i set successfully mpls between cisco ,router1 and router 2.

but i want vpls tunnel between routerboard 2 and cisco 7200vxr..

please help.

maybe, http://wiki.mikrotik.com/wiki/Cisco_VPLS can help?..

no

i think its the only way (gre support) to connect mikrotik AP to cisco pppoe server over routed network

ios on 7200 ?
get ios for Service providers.

Cisco IOS Software, 7200 Software (C7200-P-M), Version 12.2(25)S8

but i think has no vpls support

According to the Cisco Feature Navigator (http://cisco.com/go/fn) VPLS is only available on the 7600, 6500, CRS-1 and 12000 platforms.