diff --git a/dlls/user32/controls.h b/dlls/user32/controls.h
index 72a65a042e7..35be6450739 100644
--- a/dlls/user32/controls.h
+++ b/dlls/user32/controls.h
@@ -35,6 +35,7 @@ enum builtin_winprocs
 {
     WINPROC_BUTTON = 0,
     WINPROC_COMBO,
+    WINPROC_DIALOG,
     WINPROC_EDIT,
     WINPROC_LISTBOX,
     WINPROC_SCROLLBAR,
diff --git a/dlls/user32/dialog.c b/dlls/user32/dialog.c
index b6989a6a54d..1309c09f455 100644
--- a/dlls/user32/dialog.c
+++ b/dlls/user32/dialog.c
@@ -97,8 +97,8 @@ const struct builtin_class_descr DIALOG_builtin_class =
 {
     (LPCWSTR)DIALOG_CLASS_ATOM, /* name */
     CS_SAVEBITS | CS_DBLCLKS, /* style  */
-    DefDlgProcA,        /* procA */
-    DefDlgProcW,        /* procW */
+    NULL,               /* procA */
+    BUILTIN_WINPROC(WINPROC_DIALOG), /* procW */
     DLGWINDOWEXTRA,     /* extra */
     IDC_ARROW,          /* cursor */
     0                   /* brush */
diff --git a/dlls/user32/winproc.c b/dlls/user32/winproc.c
index d2e75a10c42..89a1ae98126 100644
--- a/dlls/user32/winproc.c
+++ b/dlls/user32/winproc.c
@@ -66,6 +66,7 @@ static WINDOWPROC winproc_array[MAX_WINPROCS] =
 {
     { ButtonWndProcA, ButtonWndProcW },        /* WINPROC_BUTTON */
     { ComboWndProcA, ComboWndProcW },          /* WINPROC_COMBO */
+    { DefDlgProcA, DefDlgProcW },              /* WINPROC_DIALOG */
     { EditWndProcA, EditWndProcW },            /* WINPROC_EDIT */
     { ListBoxWndProcA, ListBoxWndProcW },      /* WINPROC_LISTBOX */
     { ScrollBarWndProcA, ScrollBarWndProcW },  /* WINPROC_SCROLLBAR */