diff --git a/src/iperf.h b/src/iperf.h
index f297587d1..539c4a17c 100644
--- a/src/iperf.h
+++ b/src/iperf.h
@@ -447,6 +447,7 @@ struct iperf_test
 #define MIN_INTERVAL 0.1
 #define MAX_INTERVAL 60.0
 #define MAX_TIME 86400
+#define MAX_OMIT_TIME 600
 #define MAX_BURST 1000
 #define MAX_MSS (9 * 1024)
 #define MAX_STREAMS 128
diff --git a/src/iperf_api.c b/src/iperf_api.c
index f5d07084e..c5ac43e27 100644
--- a/src/iperf_api.c
+++ b/src/iperf_api.c
@@ -1493,7 +1493,7 @@ iperf_parse_arguments(struct iperf_test *test, int argc, char **argv)
                 break;
             case 'O':
                 test->omit = atoi(optarg);
-                if (test->omit < 0 || test->omit > MAX_TIME) {
+                if (test->omit < 0 || test->omit > MAX_OMIT_TIME) {
                     i_errno = IEOMIT;
                     return -1;
                 }
diff --git a/src/iperf_error.c b/src/iperf_error.c
index 3388d376e..e06723ba6 100644
--- a/src/iperf_error.c
+++ b/src/iperf_error.c
@@ -213,7 +213,7 @@ iperf_strerror(int int_errno)
             snprintf(errstr, len, "this OS does not support sendfile");
             break;
         case IEOMIT:
-            snprintf(errstr, len, "bogus value for --omit");
+            snprintf(errstr, len, "bogus value for --omit (maximum = %d seconds)", MAX_OMIT_TIME);
             break;
         case IEUNIMP:
             snprintf(errstr, len, "an option you are trying to set is not implemented yet");