Hello all, any thoughts on how I can solve this problem?

I have two monowall boxes at two locations, each with it's own subnet, 
and I am interesting in accessing between the two subnets using IPSEC.  
I've configured the two monowall boxes according to 
http://www.m0n0.ch/wall/docbook/ipsec-tunnels.html

But here is a small twist, on the second subnet, on one of the nodes, 
running Linux, I also have a second NIC with real IP assigned to eth0.  
For some reason, I cannot seem to ping between the two.  Here is the 
complete setting:

Site 1:
    monowall
    WAN = 11.22.33.17 (not real ip of course)
    LAN = 192.168.1.0/24
    compute nodes
    192.168.1.{4,5,6}

Site 2:
    monowall
    WAN = 99.88.77.65 (not real ip of course)
    LAN = 192.168.2.0/24
    compute node
       eth1: 192.168.2.1
       eth0: 99.88.77.66 (not real ip of course)

I was able to connect ping between the two nodes when I did not have 
eth0 on the compute node at site 2.  Any thoughts or suggestion would be 
greatly appreicated.  Oh btw, the routing table is as followed:

route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
99.88.77.64     0.0.0.0         255.255.255.224 U     0      0        0 eth0
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         99.88.77.65     0.0.0.0         UG    0      0        0 eth0

(not using real ip's of course)

Thanks,

John