diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index a258868..1285abc 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -326,7 +326,7 @@
 #define USAGE \
     "\n usage: ssl_server2 param=<>...\n"                   \
     "\n acceptable parameters:\n"                           \
-    "    server_addr=%%d      default: (all interfaces)\n"  \
+    "    server_addr=%%s      default: (all interfaces)\n"  \
     "    server_port=%%d      default: 4433\n"              \
     "    debug_level=%%d      default: 0 (disabled)\n"      \
     "    nbio=%%d             default: 0 (blocking I/O)\n"  \