diff --git a/pstsdk/disk/disk.h b/pstsdk/disk/disk.h
index b3058d7..60c08b1 100644
--- a/pstsdk/disk/disk.h
+++ b/pstsdk/disk/disk.h
@@ -1341,12 +1341,14 @@ struct bth_header
 template<typename K>
 struct bth_nonleaf_entry
 {
-    K key;        //!< Key of the lower level page
-    heap_id page; //!< Heap id of the lower level page
-} PSTSDK_MS_STRUCT;
+    K key;                       //!< Key of the lower level page
+    heap_id page PSTSDK_PACK_2;  //!< Heap id of the lower level page
+};
 #pragma pack()
 //! \cond static_asserts
 static_assert(sizeof(bth_nonleaf_entry<ushort>) == 6, "bth_nonleaf_entry<ushort> incorrect size");
+static_assert(offsetof(bth_nonleaf_entry<ushort>, key) == 0, "bth_nonleaf_entry<ushort> key at incorrect offset");
+static_assert(offsetof(bth_nonleaf_entry<ushort>, page) == 2, "bth_nonleaf_entry<ushort> page at incorrect offset");
 //! \endcond
 
 //! \brief Entries which make up a "leaf" BTH allocation
diff --git a/pstsdk/ltp/heap.h b/pstsdk/ltp/heap.h
index 6d3128e..9d6512a 100644
--- a/pstsdk/ltp/heap.h
+++ b/pstsdk/ltp/heap.h
@@ -468,7 +468,8 @@ inline std::tr1::shared_ptr<pstsdk::bth_nonleaf_node<K,V> > pstsdk::bth_node<K,V
 
     for(uint i = 0; i < num_entries; ++i)
     {
-        child_nodes.push_back(std::make_pair(pbth_nonleaf_node->entries[i].key, pbth_nonleaf_node->entries[i].page));
+        heap_id page = pbth_nonleaf_node->entries[i].page;
+        child_nodes.push_back(std::make_pair(pbth_nonleaf_node->entries[i].key, page));
     }
 
 #ifndef BOOST_NO_RVALUE_REFERENCES
diff --git a/pstsdk/util/primitives.h b/pstsdk/util/primitives.h
index 0fad923..6121ccd 100644
--- a/pstsdk/util/primitives.h
+++ b/pstsdk/util/primitives.h
@@ -53,8 +53,10 @@
 // '#pragma ms_struct on', but it fails on at least some Linux systems.
 #ifdef __GNUC__
 #define PSTSDK_MS_STRUCT __attribute__((ms_struct))
+#define PSTSDK_PACK_2 __attribute__((packed, aligned(2)))
 #else
 #define PSTSDK_MS_STRUCT
+#define PSTSDK_PACK_2
 #endif
 
 namespace pstsdk