I'm not sure I have a good picture of the LAN segments and connections.
- Your MPLS is connected to a switch along with an interface on the SSG5.
- Is the next hop address to send traffic to the MPLS service in the same subnet as the local clients or different?
- Is this an isolated point to point link (ideal)
- Or is this switch also the same VLAN that your local computer clients are in.
- Is the SSG the default gateway for the local clients or the MPLS service