diff --git a/include/media/IOMX.h b/include/media/IOMX.h
index 84fdf83..7023453 100644
--- a/include/media/IOMX.h
+++ b/include/media/IOMX.h
@@ -25,6 +25,8 @@
 #include <utils/List.h>
 #include <utils/String8.h>
 
+#include <list>
+
 #include <media/hardware/MetadataBufferType.h>
 
 #include <OMX_Core.h>
@@ -231,7 +233,8 @@
 public:
     DECLARE_META_INTERFACE(OMXObserver);
 
-    virtual void onMessage(const omx_message &msg) = 0;
+    // Handle (list of) messages.
+    virtual void onMessages(const std::list<omx_message> &messages) = 0;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/include/media/stagefright/ACodec.h b/include/media/stagefright/ACodec.h
index f7a3df7..d4891a1 100644
--- a/include/media/stagefright/ACodec.h
+++ b/include/media/stagefright/ACodec.h
@@ -109,6 +109,7 @@
     enum {
         kWhatSetup                   = 'setu',
         kWhatOMXMessage              = 'omx ',
+        kWhatOMXMessageList          = 'omxL',
         kWhatInputBufferFilled       = 'inpF',
         kWhatOutputBufferDrained     = 'outD',
         kWhatShutdown                = 'shut',