diff --git a/reactos/ntoskrnl/ex/sysinfo.c b/reactos/ntoskrnl/ex/sysinfo.c
index 6c358be4b25..be41eaae3ae 100644
--- a/reactos/ntoskrnl/ex/sysinfo.c
+++ b/reactos/ntoskrnl/ex/sysinfo.c
@@ -1391,7 +1391,7 @@ QSI_DEF(SystemTimeAdjustmentInformation)
     /* Give time values to our caller */
     TimeInfo->TimeIncrement = KeMaximumIncrement;
     TimeInfo->TimeAdjustment = KeTimeAdjustment;
-    TimeInfo->Enable = TRUE;
+    TimeInfo->Enable = !KiTimeAdjustmentEnabled;
 
     return STATUS_SUCCESS;
 }
@@ -1399,8 +1399,8 @@ QSI_DEF(SystemTimeAdjustmentInformation)
 SSI_DEF(SystemTimeAdjustmentInformation)
 {
     KPROCESSOR_MODE PreviousMode = KeGetPreviousMode();
-    /*PSYSTEM_SET_TIME_ADJUST_INFORMATION TimeInfo =
-        (PSYSTEM_SET_TIME_ADJUST_INFORMATION)Buffer;*/
+    PSYSTEM_SET_TIME_ADJUST_INFORMATION TimeInfo =
+        (PSYSTEM_SET_TIME_ADJUST_INFORMATION)Buffer;
 
     /* Check size of a buffer, it must match our expectations */
     if (sizeof(SYSTEM_SET_TIME_ADJUST_INFORMATION) != Size)
@@ -1416,9 +1416,24 @@ SSI_DEF(SystemTimeAdjustmentInformation)
         }
     }
 
-    /* TODO: Set time adjustment information */
-    DPRINT1("Setting of SystemTimeAdjustmentInformation is not implemented yet!\n");
-    return STATUS_NOT_IMPLEMENTED;
+    /* FIXME: behaviour suggests the member be named 'Disable' */
+    if (TimeInfo->Enable)
+    {
+        /* Disable time adjustment and set default value */
+        KiTimeAdjustmentEnabled = FALSE;
+        KeTimeAdjustment = KeMaximumIncrement;
+    }
+    else
+    {
+        /* Check if a valid time adjustment value is given */
+        if (TimeInfo->TimeAdjustment == 0) return STATUS_INVALID_PARAMETER_2;
+
+        /* Enable time adjustment and set the adjustment value */
+        KiTimeAdjustmentEnabled = TRUE;
+        KeTimeAdjustment = TimeInfo->TimeAdjustment;
+    }
+
+    return STATUS_SUCCESS;
 }
 
 /* Class 29 - Summary Memory Information */
diff --git a/reactos/ntoskrnl/include/internal/ke.h b/reactos/ntoskrnl/include/internal/ke.h
index be1423e2225..2d29738cdee 100644
--- a/reactos/ntoskrnl/include/internal/ke.h
+++ b/reactos/ntoskrnl/include/internal/ke.h
@@ -132,6 +132,7 @@ extern PVOID KeUserExceptionDispatcher;
 extern PVOID KeRaiseUserExceptionDispatcher;
 extern ULONG KeTimeIncrement;
 extern ULONG KeTimeAdjustment;
+extern BOOLEAN KiTimeAdjustmentEnabled;
 extern LONG KiTickOffset;
 extern ULONG_PTR KiBugCheckData[5];
 extern ULONG KiFreezeFlag;
diff --git a/reactos/ntoskrnl/ke/time.c b/reactos/ntoskrnl/ke/time.c
index 257f51043b8..49ca79d3a4b 100644
--- a/reactos/ntoskrnl/ke/time.c
+++ b/reactos/ntoskrnl/ke/time.c
@@ -16,6 +16,7 @@
 
 LONG KiTickOffset;
 ULONG KeTimeAdjustment;
+BOOLEAN KiTimeAdjustmentEnabled = FALSE;
 
 /* FUNCTIONS ******************************************************************/
 
@@ -23,12 +24,12 @@ VOID
 FASTCALL
 KeUpdateSystemTime(IN PKTRAP_FRAME TrapFrame,
                    IN ULONG Increment,
-                   IN KIRQL Irql)                   
+                   IN KIRQL Irql)
 {
     PKPRCB Prcb = KeGetCurrentPrcb();
     ULARGE_INTEGER CurrentTime, InterruptTime;
     ULONG Hand, OldTickCount;
-    
+
     /* Add the increment time to the shared data */
     InterruptTime.HighPart = SharedUserData->InterruptTime.High1Time;
     InterruptTime.LowPart = SharedUserData->InterruptTime.LowPart;
@@ -36,10 +37,10 @@ KeUpdateSystemTime(IN PKTRAP_FRAME TrapFrame,
     SharedUserData->InterruptTime.High1Time = InterruptTime.HighPart;
     SharedUserData->InterruptTime.LowPart = InterruptTime.LowPart;
     SharedUserData->InterruptTime.High2Time = InterruptTime.HighPart;
-    
+
     /* Update tick count */
     InterlockedExchangeAdd(&KiTickOffset, -(LONG)Increment);
-    
+
     /* Check for incomplete tick */
     OldTickCount = KeTickCount.LowPart;
     if (KiTickOffset <= 0)
@@ -51,7 +52,7 @@ KeUpdateSystemTime(IN PKTRAP_FRAME TrapFrame,
         SharedUserData->SystemTime.High2Time = CurrentTime.HighPart;
         SharedUserData->SystemTime.LowPart = CurrentTime.LowPart;
         SharedUserData->SystemTime.High1Time = CurrentTime.HighPart;
-        
+
         /* Update the tick count */
         CurrentTime.HighPart = KeTickCount.High1Time;
         CurrentTime.LowPart = OldTickCount;
@@ -59,50 +60,50 @@ KeUpdateSystemTime(IN PKTRAP_FRAME TrapFrame,
         KeTickCount.High2Time = CurrentTime.HighPart;
         KeTickCount.LowPart = CurrentTime.LowPart;
         KeTickCount.High1Time = CurrentTime.HighPart;
-        
+
         /* Update it in the shared user data */
         SharedUserData->TickCount.High2Time = CurrentTime.HighPart;
         SharedUserData->TickCount.LowPart = CurrentTime.LowPart;
         SharedUserData->TickCount.High1Time = CurrentTime.HighPart;
-        
+
         /* Check for timer expiration */
         Hand = OldTickCount & (TIMER_TABLE_SIZE - 1);
         if (KiTimerTableListHead[Hand].Time.QuadPart <= InterruptTime.QuadPart)
         {
             /* Check if we are already doing expiration */
             if (!Prcb->TimerRequest)
-            {                        
+            {
                 /* Request a DPC to handle this */
                 Prcb->TimerRequest = (ULONG_PTR)TrapFrame;
                 Prcb->TimerHand = Hand;
                 HalRequestSoftwareInterrupt(DISPATCH_LEVEL);
             }
         }
-        
+
         /* Check for expiration with the new tick count as well */
         OldTickCount++;
     }
-    
+
     /* Check for timer expiration */
     Hand = OldTickCount & (TIMER_TABLE_SIZE - 1);
     if (KiTimerTableListHead[Hand].Time.QuadPart <= InterruptTime.QuadPart)
     {
         /* Check if we are already doing expiration */
         if (!Prcb->TimerRequest)
-        {                        
+        {
             /* Request a DPC to handle this */
             Prcb->TimerRequest = (ULONG_PTR)TrapFrame;
             Prcb->TimerHand = Hand;
             HalRequestSoftwareInterrupt(DISPATCH_LEVEL);
         }
     }
-    
+
     /* Check if this was a full tick */
     if (KiTickOffset <= 0)
     {
         /* Update the tick offset */
         KiTickOffset += KeMaximumIncrement;
-        
+
         /* Update system runtime */
         KeUpdateRunTime(TrapFrame, Irql);
     }
@@ -111,7 +112,7 @@ KeUpdateSystemTime(IN PKTRAP_FRAME TrapFrame,
         /* Increase interrupt count and exit */
         Prcb->InterruptCount++;
     }
-    
+
     /* Disable interrupts and end the interrupt */
     KiEndInterrupt(Irql, TrapFrame);
 }
@@ -126,7 +127,7 @@ KeUpdateRunTime(IN PKTRAP_FRAME TrapFrame,
 
     /* Increase interrupt count */
     Prcb->InterruptCount++;
-    
+
     /* Check if we came from user mode */
 #ifndef _M_ARM
     if ((TrapFrame->SegCs & MODE_MASK) || (TrapFrame->EFlags & EFLAGS_V86_MASK))
@@ -158,19 +159,19 @@ KeUpdateRunTime(IN PKTRAP_FRAME TrapFrame,
             Prcb->DpcTime++;
         }
     }
-    
+
     /* Update DPC rates */
     Prcb->DpcRequestRate = ((Prcb->DpcData[0].DpcCount - Prcb->DpcLastCount) +
                             Prcb->DpcRequestRate) >> 1;
     Prcb->DpcLastCount = Prcb->DpcData[0].DpcCount;
-    
+
     /* Check if the queue is large enough */
     if ((Prcb->DpcData[0].DpcQueueDepth) && !(Prcb->DpcRoutineActive))
     {
         /* Request a DPC */
         Prcb->AdjustDpcThreshold = KiAdjustDpcThreshold;
         HalRequestSoftwareInterrupt(DISPATCH_LEVEL);
-        
+
         /* Fix the maximum queue depth */
         if ((Prcb->DpcRequestRate < KiIdealDpcRate) &&
             (Prcb->MaximumDpcQueueDepth > 1))
@@ -193,7 +194,7 @@ KeUpdateRunTime(IN PKTRAP_FRAME TrapFrame,
             }
         }
     }
-    
+
     /* Decrement the thread quantum */
     Thread->Quantum -= CLOCK_QUANTUM_DECREMENT;