diff --git a/composer.json b/composer.json
index 68ca83f..d0844ea 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
         "php": "^7.1",
         "ext-json": "*",
         "ext-dom": "*",
-        "ext-intl": "*",
+        "symfony/polyfill-intl-idn": "1.*",
         "ralouphie/mimey": "^2.1",
         "psr/http-message": "^1.0",
         "mensbeam/mimesniff": "^0.2.0",