diff --git a/reactos/include/ndk/pstypes.h b/reactos/include/ndk/pstypes.h
index 6ee5b215b31..aa37197fd75 100644
--- a/reactos/include/ndk/pstypes.h
+++ b/reactos/include/ndk/pstypes.h
@@ -102,6 +102,12 @@ typedef struct _CURDIR
     PVOID Handle;
 } CURDIR, *PCURDIR;
 
+typedef struct _DESCRIPTOR_TABLE_ENTRY
+{
+    ULONG Selector;
+    LDT_ENTRY Descriptor;
+} DESCRIPTOR_TABLE_ENTRY, *PDESCRIPTOR_TABLE_ENTRY;
+
 typedef struct _PEB_FREE_BLOCK 
 {
     struct _PEB_FREE_BLOCK* Next;
diff --git a/reactos/include/ndk/rtlfuncs.h b/reactos/include/ndk/rtlfuncs.h
index 7962f8ba168..4e5336fa641 100644
--- a/reactos/include/ndk/rtlfuncs.h
+++ b/reactos/include/ndk/rtlfuncs.h
@@ -631,6 +631,30 @@ RtlAreBitsSet(
   IN ULONG  StartingIndex,
   IN ULONG  Length); 
 
+VOID
+STDCALL
+RtlClearBits (
+	IN	PRTL_BITMAP	BitMapHeader,
+	IN	ULONG		StartingIndex,
+	IN	ULONG		NumberToClear
+	);
+
+ULONG
+STDCALL
+RtlFindClearBits (
+	PRTL_BITMAP	BitMapHeader,
+	ULONG		NumberToFind,
+	ULONG		HintIndex
+	);
+
+ULONG
+STDCALL
+RtlFindClearBitsAndSet (
+	PRTL_BITMAP	BitMapHeader,
+	ULONG		NumberToFind,
+	ULONG		HintIndex
+	);
+    
 NTSTATUS
 STDCALL
 RtlMultiByteToUnicodeN (