diff --git a/dlls/ttydrv/ttydrv.spec b/dlls/ttydrv/ttydrv.spec
index 8a14613f7f4..00675d2c35a 100644
--- a/dlls/ttydrv/ttydrv.spec
+++ b/dlls/ttydrv/ttydrv.spec
@@ -27,7 +27,7 @@ debug_channels (ttydrv)
 @ cdecl GetScreenSaveTimeout() TTYDRV_GetScreenSaveTimeout
 @ cdecl SetScreenSaveTimeout(long) TTYDRV_SetScreenSaveTimeout
 @ cdecl LoadOEMResource(long long) TTYDRV_LoadOEMResource
-@ cdecl CreateWindow(long ptr) TTYDRV_CreateWindow
+@ cdecl CreateWindow(long ptr long) TTYDRV_CreateWindow
 @ cdecl DestroyWindow(long) TTYDRV_DestroyWindow
 @ cdecl GetDC(long long long long) TTYDRV_GetDC
 @ cdecl SetWindowPos(ptr) TTYDRV_SetWindowPos
diff --git a/dlls/ttydrv/wnd.c b/dlls/ttydrv/wnd.c
index b0ae7e11d0e..09e72445e16 100644
--- a/dlls/ttydrv/wnd.c
+++ b/dlls/ttydrv/wnd.c
@@ -30,7 +30,7 @@ WND_DRIVER TTYDRV_WND_Driver =
 /**********************************************************************
  *		CreateWindow   (TTYDRV.@)
  */
-BOOL TTYDRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs )
+BOOL TTYDRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs, BOOL unicode )
 {
     BOOL ret;
 
@@ -65,7 +65,7 @@ BOOL TTYDRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs )
     FIXME("(%x): stub\n", hwnd);
 #endif /* defined(WINE_CURSES) */
 
-    if (IsWindowUnicode( hwnd ))
+    if (unicode)
     {
         ret = SendMessageW( hwnd, WM_NCCREATE, 0, (LPARAM)cs );
         if (ret) ret = (SendMessageW( hwnd, WM_CREATE, 0, (LPARAM)cs ) != -1);
diff --git a/dlls/x11drv/window.c b/dlls/x11drv/window.c
index 2b54382648d..da943d4d947 100644
--- a/dlls/x11drv/window.c
+++ b/dlls/x11drv/window.c
@@ -769,7 +769,7 @@ BOOL X11DRV_DestroyWindow( HWND hwnd )
 /**********************************************************************
  *		CreateWindow   (X11DRV.@)
  */
-BOOL X11DRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs )
+BOOL X11DRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs, BOOL unicode )
 {
     Display *display = thread_display();
     WND *wndPtr;
@@ -788,7 +788,7 @@ BOOL X11DRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs )
     wndPtr->flags |= WIN_NATIVE;
     WIN_ReleaseWndPtr( wndPtr );
 
-    if (IsWindowUnicode( hwnd ))
+    if (unicode)
         ret = SendMessageW( hwnd, WM_NCCREATE, 0, (LPARAM)cs );
     else
         ret = SendMessageA( hwnd, WM_NCCREATE, 0, (LPARAM)cs );
@@ -830,7 +830,7 @@ BOOL X11DRV_CreateWindow( HWND hwnd, CREATESTRUCTA *cs )
     X11DRV_register_window( display, hwnd, data );
     WIN_ReleaseWndPtr( wndPtr );
 
-    if (IsWindowUnicode( hwnd ))
+    if (unicode)
         ret = (SendMessageW( hwnd, WM_CREATE, 0, (LPARAM)cs ) != -1);
     else
         ret = (SendMessageA( hwnd, WM_CREATE, 0, (LPARAM)cs ) != -1);
diff --git a/dlls/x11drv/x11drv.spec b/dlls/x11drv/x11drv.spec
index 70d3aa34e5e..d850234b3e3 100644
--- a/dlls/x11drv/x11drv.spec
+++ b/dlls/x11drv/x11drv.spec
@@ -27,7 +27,7 @@ debug_channels (bitblt bitmap clipboard cursor dinput event font gdi graphics
 @ cdecl GetScreenSaveTimeout() X11DRV_GetScreenSaveTimeout
 @ cdecl SetScreenSaveTimeout(long) X11DRV_SetScreenSaveTimeout
 @ cdecl LoadOEMResource(long long) X11DRV_LoadOEMResource
-@ cdecl CreateWindow(long ptr) X11DRV_CreateWindow
+@ cdecl CreateWindow(long ptr long) X11DRV_CreateWindow
 @ cdecl DestroyWindow(long) X11DRV_DestroyWindow
 @ cdecl GetDC(long long long long) X11DRV_GetDC
 @ cdecl EnableWindow(long long) X11DRV_EnableWindow
diff --git a/include/user.h b/include/user.h
index 51d45ac8468..8d0355d0b9f 100644
--- a/include/user.h
+++ b/include/user.h
@@ -69,7 +69,7 @@ typedef struct tagUSER_DRIVER {
     void   (*pResetSelectionOwner)(struct tagWND *, BOOL);
 
     /* windowing functions */
-    BOOL   (*pCreateWindow)(HWND,CREATESTRUCTA*);
+    BOOL   (*pCreateWindow)(HWND,CREATESTRUCTA*,BOOL);
     BOOL   (*pDestroyWindow)(HWND);
     BOOL   (*pGetDC)(HWND,HDC,HRGN,DWORD);
     BOOL   (*pEnableWindow)(HWND,BOOL);
diff --git a/windows/win.c b/windows/win.c
index 0ad24dce579..ab43058e1f7 100644
--- a/windows/win.c
+++ b/windows/win.c
@@ -615,7 +615,7 @@ BOOL WIN_CreateDesktopWindow(void)
     cs.lpszName       = NULL;
     cs.lpszClass      = DESKTOP_CLASS_ATOM;
 
-    if (!USER_Driver.pCreateWindow( hwndDesktop, &cs )) return FALSE;
+    if (!USER_Driver.pCreateWindow( hwndDesktop, &cs, FALSE )) return FALSE;
 
     pWndDesktop->flags |= WIN_NEEDS_ERASEBKGND;
     return TRUE;
@@ -704,6 +704,7 @@ static HWND WIN_CreateWindowEx( CREATESTRUCTA *cs, ATOM classAtom,
     DWORD clsStyle;
     WNDPROC winproc;
     DCE *dce;
+    BOOL unicode = (type == WIN_PROC_32W);
 
     TRACE("%s %s %08lx %08lx %d,%d %dx%d %04x %04x %08x %p\n",
           (type == WIN_PROC_32W) ? debugres_w((LPWSTR)cs->lpszName) : debugres_a(cs->lpszName), 
@@ -894,7 +895,7 @@ static HWND WIN_CreateWindowEx( CREATESTRUCTA *cs, ATOM classAtom,
     }
     else wndPtr->wIDmenu = (UINT)cs->hMenu;
 
-    if (!USER_Driver.pCreateWindow( wndPtr->hwndSelf, cs ))
+    if (!USER_Driver.pCreateWindow( wndPtr->hwndSelf, cs, unicode))
     {
         WARN("aborted by WM_xxCREATE!\n");
         WIN_ReleaseWndPtr(WIN_DestroyWindow( wndPtr ));