diff --git a/tester/liblinphone_tester.c b/tester/liblinphone_tester.c
index bbd1052bf..927ac8303 100644
--- a/tester/liblinphone_tester.c
+++ b/tester/liblinphone_tester.c
@@ -191,7 +191,9 @@ static const char* liblinphone_helper =
 		"\t\t\t--auth-domain <test auth domain>\n"
 		"\t\t\t--dns-hosts </etc/hosts -like file to used to override DNS names (default: tester_hosts)>\n"
 		"\t\t\t--keep-recorded-files\n"
-		"\t\t\t--disable-leak-detector\n";
+		"\t\t\t--disable-leak-detector\n"
+		"\t\t\t--6\n"
+		;
 
 int main (int argc, char *argv[])
 {