diff --git a/src/ChangeLog b/src/ChangeLog
index 08e44bd095d..45c901fb342 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2008-12-20  Jason Rumney  <jasonr@gnu.org>
+
+	* coding.c (decode_coding): Clear chars_at_source flag when using
+	charbuf.
+
 2008-12-19  Daniel Engeler  <engeler@gmail.com>
 
 	* sysdep.c (serial_configure): Fix typo.
diff --git a/src/coding.c b/src/coding.c
index e292f808597..869a2715640 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -6654,6 +6654,8 @@ decode_coding (coding)
 	     that the number of data is less than the size of
 	     coding->charbuf.  */
 	  coding->charbuf_used = 0;
+	  coding->chars_at_source = 0;
+
 	  while (nbytes-- > 0)
 	    {
 	      int c = *src++;