diff --git a/protobuf-c/protobuf-c.c b/protobuf-c/protobuf-c.c
index 32dfe11..4a870cd 100644
--- a/protobuf-c/protobuf-c.c
+++ b/protobuf-c/protobuf-c.c
@@ -155,20 +155,6 @@ ProtobufCAllocator protobuf_c_default_allocator =
   NULL          /* allocator_data */
 };
 
-/* Users should NOT modify this structure,
-   but it's difficult to prevent.
-
-   please modify protobuf_c_default_allocator instead. */
-ProtobufCAllocator protobuf_c_system_allocator =
-{
-  system_alloc,
-  system_free,
-  NULL,         /* tmp_alloc */
-  8192,         /* max_alloca */
-  NULL          /* allocator_data */
-};
-
-
 /* === buffer-simple === */
 void
 protobuf_c_buffer_simple_append (ProtobufCBuffer *buffer,
diff --git a/protobuf-c/protobuf-c.h b/protobuf-c/protobuf-c.h
index f52d7ca..5cc3674 100644
--- a/protobuf-c/protobuf-c.h
+++ b/protobuf-c/protobuf-c.h
@@ -164,12 +164,6 @@ struct _ProtobufCAllocator
  */
 extern PROTOBUF_C_API ProtobufCAllocator protobuf_c_default_allocator; /* settable */
 
-/* This is the system allocator, meaning it uses malloc() and free().
- *
- * NOTE: please do NOT modify this allocator.
- */
-extern PROTOBUF_C_API ProtobufCAllocator protobuf_c_system_allocator;  /* use malloc, free etc */
-
 /* This is the function that our default allocators call when they 
    run out-of-memory.  The default behavior of this function is to
    terminate your program. */