Dual NIC Card

We have dual NIC’s in a Windows 2000 server. We want to have them setup on the same segment. Once setup, certain programs (like our network monitoring tool, PcAnywhere) randomly get confused on which NIC to answer on. Our monitoring tool points to the primary NIC. It typically answers back on that NIC but sometimes tries to answer on the second NIC. The monitoring tool then thinks the server is down. The it just decides to start answering on the primary NIC. Is there a configuration change that can be made that will make each card independant and answer on requests sent to itself and not try to route the request out on the second card?