+#if !GTK_CHECK_VERSION(2,10,0)
+ // GTK+ can reliably detect Meta key state only since 2.10 when
+ // GDK_META_MASK was introduced -- there wasn't any way to detect it
+ // in older versions. wxGTK used GDK_MOD2_MASK for this purpose, but
+ // GDK_MOD2_MASK is documented as:
+ //
+ // the fifth modifier key (it depends on the modifier mapping of the X
+ // server which key is interpreted as this modifier)
+ //
+ // In other words, it isn't guaranteed to map to Meta. This is a real
+ // problem: it is common to map NumLock to it (in fact, it's an exception
+ // if the X server _doesn't_ use it for NumLock). So the old code caused
+ // wxKeyEvent::MetaDown() to always return true as long as NumLock was on
+ // on many systems, which broke all applications using
+ // wxKeyEvent::GetModifiers() to check modifiers state (see e.g. here:
+ // http://tinyurl.com/56lsk2).
+ //
+ // Because of this, it's better to not detect Meta key state at all than
+ // to detect it incorrectly. Hence the following #define, which causes
+ // m_metaDown to be always set to false.
+ #define GDK_META_MASK 0
+#endif
+