diff --git a/reactos/include/reactos/libs/fast486/fast486.h b/reactos/include/reactos/libs/fast486/fast486.h
index d4f3cf18a96..1f64daff688 100644
--- a/reactos/include/reactos/libs/fast486/fast486.h
+++ b/reactos/include/reactos/libs/fast486/fast486.h
@@ -515,6 +515,7 @@ struct _FAST486_STATE
     FAST486_REG GeneralRegs[FAST486_NUM_GEN_REGS];
     FAST486_SEG_REG SegmentRegs[FAST486_NUM_SEG_REGS];
     FAST486_REG InstPtr, SavedInstPtr;
+    FAST486_REG SavedStackPtr;
     FAST486_FLAGS_REG Flags;
     FAST486_TABLE_REG Gdtr, Idtr;
     FAST486_LDT_REG Ldtr;
diff --git a/reactos/lib/fast486/common.c b/reactos/lib/fast486/common.c
index 9a580af2f16..a5deaf86eb8 100644
--- a/reactos/lib/fast486/common.c
+++ b/reactos/lib/fast486/common.c
@@ -579,6 +579,9 @@ Fast486ExceptionWithErrorCode(PFAST486_STATE State,
     /* Restore the IP to the saved IP */
     State->InstPtr = State->SavedInstPtr;
 
+    /* Restore  the SP to the saved SP */
+    State->GeneralRegs[FAST486_REG_ESP] = State->SavedStackPtr;
+
     /* Get the interrupt vector */
     if (!Fast486GetIntVector(State, ExceptionCode, &IdtEntry))
     {
@@ -1040,7 +1043,7 @@ Fast486CallGate(PFAST486_STATE State,
                                OldEsp,
                                FALSE,
                                ParamBuffer,
-                               Gate->ParamCount * sizeof(ULONG)))
+                               Gate->ParamCount * (GateSize ? sizeof(ULONG) : sizeof(USHORT))))
         {
             /* Exception occurred */
             return FALSE;
diff --git a/reactos/lib/fast486/fast486.c b/reactos/lib/fast486/fast486.c
index 4db9b864c43..e2ff4562b21 100644
--- a/reactos/lib/fast486/fast486.c
+++ b/reactos/lib/fast486/fast486.c
@@ -61,7 +61,11 @@ Fast486ExecutionControl(PFAST486_STATE State, FAST486_EXEC_CMD Command)
         {
 NextInst:
             /* Check if this is a new instruction */
-            if (State->PrefixFlags == 0) State->SavedInstPtr = State->InstPtr;
+            if (State->PrefixFlags == 0)
+            {
+                State->SavedInstPtr = State->InstPtr;
+                State->SavedStackPtr = State->GeneralRegs[FAST486_REG_ESP];
+            }
 
             /* Perform an instruction fetch */
             if (!Fast486FetchByte(State, &Opcode))