diff --git a/source/include/actypes.h b/source/include/actypes.h
index c2edc18eb..b4f56f740 100644
--- a/source/include/actypes.h
+++ b/source/include/actypes.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: actypes.h - Common data types for the entire ACPI subsystem
- *       $Revision: 1.185 $
+ *       $Revision: 1.186 $
  *
  *****************************************************************************/
 
@@ -285,6 +285,13 @@ typedef UINT32                          ACPI_NAME;      /* 4-byte ACPI name */
 typedef char*                           ACPI_STRING;    /* Null terminated ASCII string */
 typedef void*                           ACPI_HANDLE;    /* Actually a ptr to an Node */
 
+typedef struct
+{
+    UINT32                                  Lo;
+    UINT32                                  Hi;
+
+} UINT64_STRUCT;
+
 
 /*
  * Acpi integer width. In ACPI version 1, integers are