diff --git a/composer.json b/composer.json
index 50f8f4dc..fd3d0eb2 100644
--- a/composer.json
+++ b/composer.json
@@ -20,14 +20,14 @@
     },
     "require": {
         "php": ">=8.0",
-        "guzzlehttp/psr7": "^2.0",
+        "guzzlehttp/psr7": "^2.5",
         "zbateson/mb-wrapper": "^2.0",
         "zbateson/stream-decorators": "^2.1",
-        "php-di/php-di": "^7.0",
+        "php-di/php-di": "^6.0|^7.0",
         "psr/log": "^1|^2|^3"
     },
     "require-dev": {
-        "phpunit/phpunit": "<10",
+        "phpunit/phpunit": "^9.6|^10",
         "friendsofphp/php-cs-fixer": "*",
         "phpstan/phpstan": "*",
         "monolog/monolog": "^2|^3"
diff --git a/src/MailMimeParser.php b/src/MailMimeParser.php
index 6a23a96f..ad7f9392 100644
--- a/src/MailMimeParser.php
+++ b/src/MailMimeParser.php
@@ -88,7 +88,6 @@ class MailMimeParser
     private static function getGlobalContainerBuilder() : ContainerBuilder
     {
         $builder = new ContainerBuilder();
-        $builder->useAttributes(true);
         foreach (self::$globalDefinitions as $def) {
             $builder->addDefinitions($def);
         }
@@ -174,7 +173,6 @@ public function __construct(
                 $builder = self::getGlobalContainerBuilder();
             } else {
                 $builder = new ContainerBuilder();
-                $builder->useAttributes(true);
                 $builder->addDefinitions(self::DEFAULT_DEFINITIONS_FILE);
             }
             if ($phpDiContainerConfig !== null) {