Do set ESP0, but after we save the old value for the V86 hack.
Modified: trunk/reactos/ntoskrnl/ke/i386/ctxswitch.S

Modified: trunk/reactos/ntoskrnl/ke/i386/ctxswitch.S
--- trunk/reactos/ntoskrnl/ke/i386/ctxswitch.S	2006-01-16 17:05:50 UTC (rev 20914)
+++ trunk/reactos/ntoskrnl/ke/i386/ctxswitch.S	2006-01-16 17:07:45 UTC (rev 20915)
@@ -170,12 +170,12 @@
 
 NoAdjust:
 
-    /* Set new ESP0 */
-    //mov [ebp+KTSS_ESP0], eax
-
     /* Save it */
     push [ebp+KTSS_ESP0]
 
+    /* Set new ESP0 */
+    mov [ebp+KTSS_ESP0], eax
+
     /* Set TEB pointer */
     mov eax, [esi+KTHREAD_TEB]
     mov [ebx+KPCR_TEB], eax