Rewrote some OSX code that had used an obj-C block, to keep the old 10.5 compilers happy.

modules/juce_events/native/juce_mac_MessageManager.mm

@@ -333,6 +333,18 @@ void MessageManager::broadcastMessage (const String& message)
 void repostCurrentNSEvent();
 void repostCurrentNSEvent()
 {
-    NSEvent* e = [NSApp currentEvent];
-    [[NSOperationQueue mainQueue] addOperationWithBlock: ^{ [NSApp postEvent: e atStart: YES]; }];
+    struct EventReposter  : public CallbackMessage
+    {
+        EventReposter() : e ([[NSApp currentEvent] retain])  {}
+        ~EventReposter()  { [e release]; }
+
+        void messageCallback() override
+        {
+            [NSApp postEvent: e atStart: YES];
+        }
+
+        NSEvent* e;
+    };
+
+    (new EventReposter())->post();
 }