[c-nsp] Cluster 2 stacks?

[andrew2 at one.net]

I've currently got a stack of 3750G's that do the majority of the
switching and static IP routing for our network.  We're building out a
new network in a nearby building and plan to connect the facilities with
underground fiber.  I'd like to install a second stack of 3750G's in the
new building and connect the two stacks via GBIC.  So far, so good.  I'd
also like to have the following abilities:

1.  Layer 2 connectivity between the two buildings, so a single IP
address within a subnet directly connected to the switches in building 1
can be picked up and moved to building 2 and plugged into the switch
stack and begin working once ARP tables update.  This part is pretty
straightforward.

2.  I'd like to have the two stacks act as one logical switch for IP
routing purposes so that layer 3 traffic doesn't necessarily have to go
between buildings if not absolutely necessary.

It seems to me that I could accomplish all this by clustering the two
stacks of 3750's, but I'm not sure if that's possible.  I can find
documentation on stacking and on clustering, but nothing about
clustering multiple stacks.  It seems feasible, but...  And, assuming
it's possible, will it accomplish what I'm looking to do?  Basically one
big logical switch that happens to have half it's ports on either end of
some GBICs?

Thanks,

Andrew