diff --git a/gtk/Gtk.metadata b/gtk/Gtk.metadata
index 280fefe61..8833b5412 100644
--- a/gtk/Gtk.metadata
+++ b/gtk/Gtk.metadata
@@ -227,6 +227,7 @@
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/method[@name='Foreach']/*/*[@name='foreach_func']" name="scope">call</attr>
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/method[@name='ForeachUnfiltered']/*/*[@name='foreach_func']" name="scope">call</attr>
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/method[@name='Load']" name="win32_utf8_variant">true</attr>
+  <attr path="/api/namespace/object[@cname='GtkAccelMap']/method[@name='LookupEntry']/*/*[@name='key']" name="pass_as">out</attr>
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/method[@name='Save']" name="win32_utf8_variant">true</attr>
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/signal[@name='Changed']" name="name">MapChanged</attr>
   <attr path="/api/namespace/object[@cname='GtkAccelMap']/signal[@name='MapChanged']/*/*[@name='p0']" name="name">accel_path</attr>