SPARC 5 Dual NIC Problems

I have a SPARC 5 with Dual NICs. One is built-in the other is an added SBUS
card. One NIC is set to a 10.0.0.2 address and the other is set 192.168.1.8.
I have placed this computer into my network which has both networks. I can
ping out the 10.0.0.2 interface and it works. I can not ping out the
192.168.1.8 interface. I have changed the MAC Address to the one NIC so that
both NICs have a different MAC address. This did not help. Could anyone help
me to understand why I can not ping the 192.168.1.1 computer yet I can ping
the 10.0.0.1 computer?

David Demland