If you need to change the host IP within Solaris 10, make sure you update all three of these files with the new settings:

• /etc/hosts
• /etc/inet/ipnodes
• /etc/defaultrouter

...otherwise things won't work :)

After you update those files you can either reboot (if you're moving the machine like I was) or just run the following command:

    $# svcadm restart network/physical