diff --git a/src/main.c b/src/main.c
index fb5c40db..a330a3b2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -396,6 +396,8 @@ int main(int argc, char **argv)
 			if (cli_cfg.pppd_plugin == NULL &&
 			    strcmp(long_options[option_index].name,
 			           "plugin") == 0) {
+				log_warn("Option --%s is deprecated, use --pppd-plugin\n",
+				         long_options[option_index].name);
 				free(cli_cfg.pppd_plugin);
 				cli_cfg.pppd_plugin = strdup(optarg);
 				break;