diff --git a/src/core/ngx_string.h b/src/core/ngx_string.h
index 1565000..db7857a 100644
--- a/src/core/ngx_string.h
+++ b/src/core/ngx_string.h
@@ -40,6 +40,7 @@
 
 
 #define ngx_strstr(s1, s2)  strstr((const char *) s1, (const char *) s2)
+#define ngx_strchr(s1, c)   strchr((const char *) s1, (int) c)
 #define ngx_strlen(s)       strlen((const char *) s)
 
 
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 49eed1b..7fa0ba3 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -2614,6 +2614,12 @@
             return NGX_CONF_ERROR;
         }
 
+        if (ngx_strchr(value[i].data, '/')) {
+            ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
+                               "server name \"%V\" has strange symbols",
+                               &value[i]);
+        }
+
         sn = ngx_array_push(&cscf->server_names);
         if (sn == NULL) {
             return NGX_CONF_ERROR;