diff --git a/xmlIO.h b/xmlIO.h
index e7b5f76..ff0114d 100644
--- a/xmlIO.h
+++ b/xmlIO.h
@@ -71,6 +71,7 @@
  * Interfaces for input
  */
 
+void	xmlRegisterDefaultInputCallbacks	(void);
 xmlParserInputBufferPtr
 	xmlAllocParserInputBuffer		(xmlCharEncoding enc);
 
@@ -108,6 +109,7 @@
 /*
  * Interfaces for output
  */
+void	xmlRegisterDefaultOutputCallbacks(void);
 xmlOutputBufferPtr
 	xmlAllocOutputBuffer		(xmlCharEncodingHandlerPtr encoder);