diff --git a/src/FedEx/ShipService/SimpleType/ServiceType.php b/src/FedEx/ShipService/SimpleType/ServiceType.php
index 31e8b1bf..0ff5f871 100644
--- a/src/FedEx/ShipService/SimpleType/ServiceType.php
+++ b/src/FedEx/ShipService/SimpleType/ServiceType.php
@@ -34,8 +34,8 @@ class ServiceType extends AbstractSimpleType
     const _INTERNATIONAL_ECONOMY = 'INTERNATIONAL_ECONOMY';
     const _INTERNATIONAL_ECONOMY_FREIGHT = 'INTERNATIONAL_ECONOMY_FREIGHT';
     const _INTERNATIONAL_FIRST = 'INTERNATIONAL_FIRST';
-    const _INTERNATIONAL_PRIORITY = 'INTERNATIONAL_PRIORITY';
-    const _INTERNATIONAL_PRIORITY_EXPRESS = 'INTERNATIONAL_PRIORITY_EXPRESS';
+    const _INTERNATIONAL_PRIORITY = 'FEDEX_INTERNATIONAL_PRIORITY';
+    const _INTERNATIONAL_PRIORITY_EXPRESS = 'FEDEX_INTERNATIONAL_PRIORITY_EXPRESS';
     const _INTERNATIONAL_PRIORITY_FREIGHT = 'INTERNATIONAL_PRIORITY_FREIGHT';
     const _PRIORITY_OVERNIGHT = 'PRIORITY_OVERNIGHT';
     const _SAME_DAY = 'SAME_DAY';