Firewall that supports HighAvailability and Spanning Tree

Question

I'm looking for a firewall appliance that supports high availability and spanning tree.

I have two ha-cluster nodes and I'd like to protect them with a firewall. To avoid a single point of failure, I'd like to have two ha-capable firewalls. And since I need redundant switches too the firewall must support the spanning tree protocol.

My preferred setup:

        +------------+  +----------+  +--------------+
lan 1 --| firewall 1 |--| switch 1 |--| ha cluster 1 |
        +------------+  +----------+  +--------------+
                      \/     |
                      /\     |
        +------------+  +----------+  +--------------+
lan 2 --| firewall 2 |--| switch 2 |--| ha cluster 2 |
        +------------+  +----------+  +--------------+

Answer 1

Cisco ASAs and 65xx-series FWSM's can do this.