diff --git a/contrib/ipfilter/tools/ippool.c b/contrib/ipfilter/tools/ippool.c
index 8218df9472b8..d326ec094208 100644
--- a/contrib/ipfilter/tools/ippool.c
+++ b/contrib/ipfilter/tools/ippool.c
@@ -298,7 +298,10 @@ poolcommand(remove, argc, argv)
 			opts |= OPT_NORESOLVE;
 			break;
 		case 'S' :
-			iph.iph_seed = atoi(optarg);
+			if (remove == 0)
+				iph.iph_seed = atoi(optarg);
+			else
+				usage(argv[0]);
 			break;
 		case 'v' :
 			opts |= OPT_VERBOSE;