diff --git a/dlls/kernel/time.c b/dlls/kernel/time.c
index e3231f504f2..99363fb0bd4 100644
--- a/dlls/kernel/time.c
+++ b/dlls/kernel/time.c
@@ -470,3 +470,29 @@ int WINAPI	SetCalendarInfoW(LCID Locale, CALID Calendar, CALTYPE CalType, LPCWST
 	  Locale, Calendar, CalType, debugstr_w(lpCalData));
     return 0;
 }
+
+/*********************************************************************
+ *      LocalFileTimeToFileTime                         (KERNEL32.@)
+ */
+BOOL WINAPI LocalFileTimeToFileTime( const FILETIME *localft,
+                                       LPFILETIME utcft )
+{
+    NTSTATUS status;
+    if ((status = RtlLocalTimeToSystemTime((PLARGE_INTEGER)localft,
+                                           (PLARGE_INTEGER)utcft)))
+        SetLastError( RtlNtStatusToDosError(status) );
+    return !status;
+}
+
+/*********************************************************************
+ *      FileTimeToLocalFileTime                         (KERNEL32.@)
+ */
+BOOL WINAPI FileTimeToLocalFileTime( const FILETIME *utcft,
+                                       LPFILETIME localft )
+{
+    NTSTATUS status;
+    if ((status = RtlSystemTimeToLocalTime((PLARGE_INTEGER)utcft,
+                                           (PLARGE_INTEGER)localft)))
+        SetLastError( RtlNtStatusToDosError(status) );
+    return !status;
+}
diff --git a/dlls/ntdll/ntdll.spec b/dlls/ntdll/ntdll.spec
index e32e0807377..7a299f28dc1 100644
--- a/dlls/ntdll/ntdll.spec
+++ b/dlls/ntdll/ntdll.spec
@@ -450,7 +450,7 @@
 @ stdcall RtlLengthRequiredSid(long) RtlLengthRequiredSid
 @ stdcall RtlLengthSecurityDescriptor(ptr) RtlLengthSecurityDescriptor
 @ stdcall RtlLengthSid(ptr) RtlLengthSid
-@ stub RtlLocalTimeToSystemTime
+@ stdcall RtlLocalTimeToSystemTime(ptr ptr) RtlLocalTimeToSystemTime
 @ stdcall RtlLockHeap(long) RtlLockHeap
 @ stub RtlLookupElementGenericTable
 @ stdcall RtlMakeSelfRelativeSD(ptr ptr ptr) RtlMakeSelfRelativeSD
@@ -521,7 +521,7 @@
 @ stdcall RtlSubAuthoritySid(ptr long) RtlSubAuthoritySid
 @ stub RtlSubtreePredecessor
 @ stub RtlSubtreeSuccessor
-@ stdcall RtlSystemTimeToLocalTime (long long) RtlSystemTimeToLocalTime
+@ stdcall RtlSystemTimeToLocalTime(ptr ptr) RtlSystemTimeToLocalTime
 @ stdcall RtlTimeFieldsToTime(ptr ptr) RtlTimeFieldsToTime
 @ stdcall RtlTimeToElapsedTimeFields(long long) RtlTimeToElapsedTimeFields
 @ stdcall RtlTimeToSecondsSince1970(ptr ptr) RtlTimeToSecondsSince1970
diff --git a/dlls/ntdll/time.c b/dlls/ntdll/time.c
index 0862967b3bd..c14dcd80fdc 100644
--- a/dlls/ntdll/time.c
+++ b/dlls/ntdll/time.c
@@ -414,6 +414,29 @@ BOOLEAN WINAPI RtlTimeFieldsToTime(
 }
 /************ end of code by Rex Jolliff (rex@lvcablemodem.com) ***************/
 
+/******************************************************************************
+ *        RtlLocalTimeToSystemTime [NTDLL.@]
+ *
+ * Converts local time to system time.
+ *
+ * PARAMS:
+ *   LocalTime [I]: Localtime to convert.
+ *   SystemTime [O]: SystemTime of the supplied localtime.
+ *
+ * RETURNS:
+ *   Status.
+ */
+NTSTATUS WINAPI RtlLocalTimeToSystemTime( const LARGE_INTEGER *LocalTime,
+                                          PLARGE_INTEGER SystemTime)
+{
+    TIME_ZONE_INFORMATION tzinfo;
+
+    TRACE("(%p, %p)\n", LocalTime, SystemTime);
+
+    RtlQueryTimeZoneInformation(&tzinfo);
+    SystemTime->QuadPart = LocalTime->QuadPart + tzinfo.Bias * 60 * (LONGLONG)10000000;
+    return STATUS_SUCCESS;
+}
 
 /******************************************************************************
  *       RtlSystemTimeToLocalTime [NTDLL.@]
@@ -427,13 +450,16 @@ BOOLEAN WINAPI RtlTimeFieldsToTime(
  * RETURNS:
  *   Nothing.
  */
-VOID WINAPI RtlSystemTimeToLocalTime(
-	IN  PLARGE_INTEGER SystemTime,
-	OUT PLARGE_INTEGER LocalTime)
+NTSTATUS WINAPI RtlSystemTimeToLocalTime( const LARGE_INTEGER *SystemTime,
+                                          PLARGE_INTEGER LocalTime )
 {
-	FIXME("(%p, %p),stub!\n",SystemTime,LocalTime);
+    TIME_ZONE_INFORMATION tzinfo;
 
-	memcpy (LocalTime, SystemTime, sizeof (PLARGE_INTEGER));
+    TRACE("(%p, %p)\n", SystemTime, LocalTime);
+
+    RtlQueryTimeZoneInformation(&tzinfo);
+    LocalTime->QuadPart = SystemTime->QuadPart - tzinfo.Bias * 60 * (LONGLONG)10000000;
+    return STATUS_SUCCESS;
 }
 
 /******************************************************************************
diff --git a/files/dos_fs.c b/files/dos_fs.c
index 35ffd07ac20..73207a29738 100644
--- a/files/dos_fs.c
+++ b/files/dos_fs.c
@@ -2481,56 +2481,6 @@ BOOL WINAPI FileTimeToDosDateTime( const FILETIME *ft, LPWORD fatdate,
     return TRUE;
 }
 
-
-/***********************************************************************
- *           LocalFileTimeToFileTime   (KERNEL32.@)
- */
-BOOL WINAPI LocalFileTimeToFileTime( const FILETIME *localft,
-                                       LPFILETIME utcft )
-{
-    struct tm *xtm;
-    DWORD remainder;
-    time_t utctime;
-
-    /* Converts from local to UTC. */
-    time_t localtime = DOSFS_FileTimeToUnixTime( localft, &remainder );
-    xtm = gmtime( &localtime );
-    utctime = mktime(xtm);
-    if(xtm->tm_isdst > 0) utctime-=3600;
-    DOSFS_UnixTimeToFileTime( utctime, utcft, remainder );
-    return TRUE;
-}
-
-
-/***********************************************************************
- *           FileTimeToLocalFileTime   (KERNEL32.@)
- */
-BOOL WINAPI FileTimeToLocalFileTime( const FILETIME *utcft,
-                                       LPFILETIME localft )
-{
-    DWORD remainder;
-    /* Converts from UTC to local. */
-    time_t unixtime = DOSFS_FileTimeToUnixTime( utcft, &remainder );
-#ifdef HAVE_TIMEGM
-    struct tm *xtm = localtime( &unixtime );
-    time_t localtime;
-
-    localtime = timegm(xtm);
-    DOSFS_UnixTimeToFileTime( localtime, localft, remainder );
-
-#else
-    struct tm *xtm;
-    time_t time;
-
-    xtm = gmtime( &unixtime );
-    time = mktime(xtm);
-    if(xtm->tm_isdst > 0) time-=3600;
-    DOSFS_UnixTimeToFileTime( 2*unixtime-time, localft, remainder );
-#endif
-    return TRUE;
-}
-
-
 /***********************************************************************
  *           FileTimeToSystemTime   (KERNEL32.@)
  */
diff --git a/include/winternl.h b/include/winternl.h
index f0db2bbbe5e..44b885f2665 100644
--- a/include/winternl.h
+++ b/include/winternl.h
@@ -992,7 +992,7 @@ NTSTATUS  WINAPI RtlLeaveCriticalSection(RTL_CRITICAL_SECTION *);
 DWORD     WINAPI RtlLengthRequiredSid(DWORD);
 ULONG     WINAPI RtlLengthSecurityDescriptor(PSECURITY_DESCRIPTOR);
 DWORD     WINAPI RtlLengthSid(PSID);
-NTSTATUS  WINAPI RtlLocalTimeToSystemTime(PLARGE_INTEGER,PLARGE_INTEGER);
+NTSTATUS  WINAPI RtlLocalTimeToSystemTime(const LARGE_INTEGER*,PLARGE_INTEGER);
 BOOLEAN   WINAPI RtlLockHeap(HANDLE);
 
 NTSTATUS  WINAPI RtlMakeSelfRelativeSD(PSECURITY_DESCRIPTOR,PSECURITY_DESCRIPTOR,LPDWORD);
@@ -1034,7 +1034,7 @@ NTSTATUS  WINAPI RtlSetTimeZoneInformation(const TIME_ZONE_INFORMATION*);
 ULONG     WINAPI RtlSizeHeap(HANDLE,ULONG,PVOID);
 LPDWORD   WINAPI RtlSubAuthoritySid(PSID,DWORD);
 LPBYTE    WINAPI RtlSubAuthorityCountSid(PSID);
-void      WINAPI RtlSystemTimeToLocalTime(PLARGE_INTEGER,PLARGE_INTEGER);
+NTSTATUS  WINAPI RtlSystemTimeToLocalTime(const LARGE_INTEGER*,PLARGE_INTEGER);
 
 void      WINAPI RtlTimeToTimeFields(const LARGE_INTEGER*,PTIME_FIELDS);
 BOOLEAN   WINAPI RtlTimeFieldsToTime(PTIME_FIELDS,PLARGE_INTEGER);