--- ethernet.subr	2008-01-31 21:15:35.000000000 -0800
+++ ethernet-mod.subr	2008-01-31 21:17:52.000000000 -0800
@@ -63,6 +63,11 @@ ethernet_up() {
             fi 
         fi
         ;;
+    # If IP is not dhcp or static, print an error
+    *)
+	err_append "Could not bring interface up, IP=() must be dhcp or static"
+        return 1
+	;;
     esac
 
     # set the hostname