diff --git a/dlls/kernel32/kernel32.spec b/dlls/kernel32/kernel32.spec
index 72a09c53c8f..0324e90201b 100644
--- a/dlls/kernel32/kernel32.spec
+++ b/dlls/kernel32/kernel32.spec
@@ -832,7 +832,7 @@
 @ stdcall GetSystemPreferredUILanguages(long ptr ptr ptr)
 @ stdcall GetSystemRegistryQuota(ptr ptr)
 @ stdcall -import GetSystemTime(ptr)
-@ stdcall GetSystemTimeAdjustment(ptr ptr ptr)
+@ stdcall -import GetSystemTimeAdjustment(ptr ptr ptr)
 @ stdcall -import GetSystemTimeAsFileTime(ptr)
 @ stdcall -import GetSystemTimePreciseAsFileTime(ptr)
 @ stdcall -import GetSystemTimes(ptr ptr ptr)
@@ -1445,7 +1445,7 @@
 @ stdcall -import SetSystemFileCacheSize(long long long)
 @ stdcall SetSystemPowerState(long long)
 @ stdcall -import SetSystemTime(ptr)
-@ stdcall SetSystemTimeAdjustment(long long)
+@ stdcall -import SetSystemTimeAdjustment(long long)
 @ stdcall SetTapeParameters(ptr long ptr)
 @ stdcall SetTapePosition(ptr long long long long long)
 @ stdcall SetTermsrvAppInstallMode(long)
diff --git a/dlls/kernel32/time.c b/dlls/kernel32/time.c
index 127f341adc0..4b959684c68 100644
--- a/dlls/kernel32/time.c
+++ b/dlls/kernel32/time.c
@@ -56,53 +56,6 @@ WINE_DEFAULT_DEBUG_CHANNEL(time);
 static const struct _KUSER_SHARED_DATA *user_shared_data = (struct _KUSER_SHARED_DATA *)0x7ffe0000;
 
 
-/***********************************************************************
- *           GetSystemTimeAdjustment     (KERNEL32.@)
- *
- *  Get the period between clock interrupts and the amount the clock
- *  is adjusted each interrupt so as to keep it in sync with an external source.
- *
- * PARAMS
- *  lpTimeAdjustment [out] The clock adjustment per interrupt in 100's of nanoseconds.
- *  lpTimeIncrement  [out] The time between clock interrupts in 100's of nanoseconds.
- *  lpTimeAdjustmentDisabled [out] The clock synchronisation has been disabled.
- *
- * RETURNS
- *  TRUE.
- *
- * BUGS
- *  Only the special case of disabled time adjustments is supported.
- */
-BOOL WINAPI GetSystemTimeAdjustment( PDWORD lpTimeAdjustment, PDWORD lpTimeIncrement,
-    PBOOL  lpTimeAdjustmentDisabled )
-{
-    *lpTimeAdjustment = 0;
-    *lpTimeIncrement = 10000000 / sysconf(_SC_CLK_TCK);
-    *lpTimeAdjustmentDisabled = TRUE;
-    return TRUE;
-}
-
-
-/***********************************************************************
- *              SetSystemTimeAdjustment  (KERNEL32.@)
- *
- *  Enables or disables the timing adjustments to the system's clock.
- *
- * PARAMS
- *  dwTimeAdjustment        [in] Number of units to add per clock interrupt.
- *  bTimeAdjustmentDisabled [in] Adjustment mode.
- *
- * RETURNS
- *  Success: TRUE.
- *  Failure: FALSE.
- */
-BOOL WINAPI SetSystemTimeAdjustment( DWORD dwTimeAdjustment, BOOL bTimeAdjustmentDisabled )
-{
-    /* Fake function for now... */
-    FIXME("(%08x,%d): stub !\n", dwTimeAdjustment, bTimeAdjustmentDisabled);
-    return TRUE;
-}
-
 /*********************************************************************
  *	GetCalendarInfoA				(KERNEL32.@)
  *
diff --git a/dlls/kernelbase/file.c b/dlls/kernelbase/file.c
index 905029066e4..cc792845205 100644
--- a/dlls/kernelbase/file.c
+++ b/dlls/kernelbase/file.c
@@ -3861,6 +3861,23 @@ void WINAPI DECLSPEC_HOTPATCH GetSystemTime( SYSTEMTIME *systime )
 }
 
 
+/***********************************************************************
+ *	GetSystemTimeAdjustment   (kernelbase.@)
+ */
+BOOL WINAPI DECLSPEC_HOTPATCH GetSystemTimeAdjustment( DWORD *adjust, DWORD *increment, BOOL *disabled )
+{
+    SYSTEM_TIME_ADJUSTMENT_QUERY st;
+    ULONG len;
+
+    if (!set_ntstatus( NtQuerySystemInformation( SystemTimeAdjustmentInformation, &st, sizeof(st), &len )))
+        return FALSE;
+    *adjust    = st.TimeAdjustment;
+    *increment = st.TimeIncrement;
+    *disabled  = st.TimeAdjustmentDisabled;
+    return TRUE;
+}
+
+
 /***********************************************************************
  *	GetSystemTimeAsFileTime   (kernelbase.@)
  */
@@ -3918,6 +3935,19 @@ BOOL WINAPI DECLSPEC_HOTPATCH SetSystemTime( const SYSTEMTIME *systime )
 }
 
 
+/***********************************************************************
+ *	SetSystemTimeAdjustment   (kernelbase.@)
+ */
+BOOL WINAPI DECLSPEC_HOTPATCH SetSystemTimeAdjustment( DWORD adjust, BOOL disabled )
+{
+    SYSTEM_TIME_ADJUSTMENT st;
+
+    st.TimeAdjustment = adjust;
+    st.TimeAdjustmentDisabled = disabled;
+    return set_ntstatus( NtSetSystemInformation( SystemTimeAdjustmentInformation, &st, sizeof(st) ));
+}
+
+
 /*********************************************************************
  *	SystemTimeToFileTime   (kernelbase.@)
  */
diff --git a/dlls/kernelbase/kernelbase.spec b/dlls/kernelbase/kernelbase.spec
index 15002299695..15f43db65d4 100644
--- a/dlls/kernelbase/kernelbase.spec
+++ b/dlls/kernelbase/kernelbase.spec
@@ -695,7 +695,7 @@
 @ stdcall GetSystemPreferredUILanguages(long ptr ptr ptr) kernel32.GetSystemPreferredUILanguages
 # @ stub GetSystemStateRootFolder
 @ stdcall GetSystemTime(ptr)
-@ stdcall GetSystemTimeAdjustment(ptr ptr ptr) kernel32.GetSystemTimeAdjustment
+@ stdcall GetSystemTimeAdjustment(ptr ptr ptr)
 @ stdcall GetSystemTimeAsFileTime(ptr)
 @ stdcall GetSystemTimePreciseAsFileTime(ptr)
 @ stdcall GetSystemTimes(ptr ptr ptr)
@@ -1477,7 +1477,7 @@
 @ stdcall SetStdHandleEx(long long ptr)
 @ stdcall SetSystemFileCacheSize(long long long)
 @ stdcall SetSystemTime(ptr)
-@ stdcall SetSystemTimeAdjustment(long long) kernel32.SetSystemTimeAdjustment
+@ stdcall SetSystemTimeAdjustment(long long)
 @ stdcall SetThreadContext(long ptr)
 @ stdcall SetThreadDescription(ptr wstr)
 @ stdcall SetThreadErrorMode(long ptr)