diff --git a/composer.json b/composer.json
index 50cb3b2..d1d4f8d 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
         "php": ">=5.3.0",
         "ext-curl": "*",
         "ext-json": "*",
-        "paypal/sdk-core-php": "1.4.*"        
+        "paypal/sdk-core-php": "2.4.*"        
     },
     "require-dev": {
         "phpunit/phpunit": "3.7.*"