Poor man's VRF = mpls+mce? a design/capability question

[Matt_M]

objective: span a common network or vlan from one side of my metroE network to the other.

existing network equipment: A5800's in a core distribution ring, with A5500's servicing each site.

see attached...

running ibgp from network at siteA, through the core, to siteB (so there is a layer3 hop to cross the core)

as the 5500's don't support mpls, I think the only option may be to run mce to get the traffic to the core, and setup mpls on the core 5800's.

a very open-ended question for a forum, but trying to get the most out of the manuals and looking for someone who may have come across this requirement and equipment mix.

tia

matt