diff --git a/gtk/gtkimcontextsimple.c b/gtk/gtkimcontextsimple.c
index 523f771da..2f4ddd0e6 100644
--- a/gtk/gtkimcontextsimple.c
+++ b/gtk/gtkimcontextsimple.c
@@ -859,8 +859,11 @@ gtk_im_context_simple_filter_keypress (GtkIMContext *context,
   hex_keyval = canonical_hex_keyval (event);
 
   /* If we are already in a non-hex sequence, or
-   * this keystroke is not hex modifiers + hex digit, don't filter 
-   * key events with accelerator modifiers held down.
+   * this keystroke is not hex modifiers + hex digit, don't filter
+   * key events with accelerator modifiers held down. We only treat
+   * Control and Alt as accel modifiers here, since Super, Hyper and
+   * Meta are often co-located with Mode_Switch, Multi_Key or
+   * ISO_Level3_Switch.
    */
   if (!have_hex_mods ||
       (n_compose > 0 && !context_simple->in_hex_sequence) || 
@@ -868,7 +871,7 @@ gtk_im_context_simple_filter_keypress (GtkIMContext *context,
       (context_simple->in_hex_sequence && !hex_keyval && 
        !is_hex_start && !is_hex_end && !is_escape && !is_backspace))
     {
-      if (event->state & (gtk_accelerator_get_default_mod_mask () & ~GDK_SHIFT_MASK) ||
+      if (event->state & (GDK_MOD1_MASK | GDK_CONTROL_MASK) ||
 	  (context_simple->in_hex_sequence && context_simple->modifiers_dropped &&
 	   (event->keyval == GDK_Return || 
 	    event->keyval == GDK_ISO_Enter ||