Index: apitests/ntdll/CMakeLists.txt
===================================================================
--- modules/rostests/apitests/ntdll/CMakeLists.txt	(revision 58904)
+++ modules/rostests/apitests/ntdll/CMakeLists.txt	(working copy)
@@ -1,6 +1,7 @@
 
 list(APPEND SOURCE
     LdrEnumResources.c
+    NtAcceptConnectPort.c
     NtAllocateVirtualMemory.c
     NtFreeVirtualMemory.c
     NtMapViewOfSection.c
Index: apitests/ntdll/NtAcceptConnectPort.c
===================================================================
--- modules/rostests/apitests/ntdll/NtAcceptConnectPort.c	(revision 0)
+++ modules/rostests/apitests/ntdll/NtAcceptConnectPort.c	(working copy)
@@ -0,0 +1,19 @@
+/*
+ * PROJECT:         ReactOS api tests
+ * LICENSE:         GPLv2+ - See COPYING in the top level directory
+ * PURPOSE:         Test for NtAcceptConnectPort
+ * PROGRAMMER:      Thomas Faber <thfabba@gmx.de>
+ */
+
+#define WIN32_NO_STATUS
+#include <wine/test.h>
+#include <ndk/lpctypes.h>
+#include <ndk/lpcfuncs.h>
+
+START_TEST(NtAcceptConnectPort)
+{
+    NTSTATUS Status;
+
+    Status = NtAcceptConnectPort(NULL, NULL, NULL, FALSE, NULL, NULL);
+    ok_hex(Status, STATUS_ACCESS_VIOLATION);
+}
Index: apitests/ntdll/testlist.c
===================================================================
--- modules/rostests/apitests/ntdll/testlist.c	(revision 58904)
+++ modules/rostests/apitests/ntdll/testlist.c	(working copy)
@@ -4,6 +4,7 @@
 #include <wine/test.h>
 
 extern void func_LdrEnumResources(void);
+extern void func_NtAcceptConnectPort(void);
 extern void func_NtAllocateVirtualMemory(void);
 extern void func_NtFreeVirtualMemory(void);
 extern void func_NtMapViewOfSection(void);
@@ -25,6 +26,7 @@
 const struct test winetest_testlist[] =
 {
     { "LdrEnumResources",               func_LdrEnumResources },
+    { "NtAcceptConnectPort",            func_NtAcceptConnectPort },
     { "NtAllocateVirtualMemory",        func_NtAllocateVirtualMemory },
     { "NtFreeVirtualMemory",            func_NtFreeVirtualMemory },
     { "NtMapViewOfSection",             func_NtMapViewOfSection },
Index: ntoskrnl/lpc/complete.c
===================================================================
--- ntoskrnl/lpc/complete.c	(revision 58910)
+++ ntoskrnl/lpc/complete.c	(working copy)
@@ -64,6 +64,27 @@
              ClientView,
              ServerView);
 
+    /* Check if the call comes from user mode */
+    if(PreviousMode != KernelMode)
+    {
+        /* Enter SEH for probing the parameters */
+       _SEH2_TRY
+        {
+            ProbeForWriteHandle(PortHandle);
+            ProbeForRead(ReplyMessage, sizeof(PORT_MESSAGE), sizeof(ULONG));
+
+            /* The following parameters are optional */
+            if(ServerView) ProbeForRead(ServerView, sizeof(PORT_VIEW), sizeof(ULONG));
+            if(ClientView) ProbeForRead(ClientView, sizeof(REMOTE_PORT_VIEW), sizeof(ULONG));
+        }
+        _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+        {
+            /* There was an exception, return the exception code */
+            _SEH2_YIELD(return _SEH2_GetExceptionCode());
+        }
+        _SEH2_END;
+    }
+
     /* Validate the size of the server view */
     if ((ServerView) && (ServerView->Length != sizeof(PORT_VIEW)))
     {