diff --git a/Misc/NEWS b/Misc/NEWS
index fea1a6a63d0..6c1fddbc17b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -75,6 +75,9 @@ Core and builtins
 Extension Modules
 -----------------
 
+- Change binascii.hexlify to accept a read-only buffer instead of only a char
+  buffer and actually follow its documentation.
+
 - Fixed a potentially invalid memory access of CJKCodecs' shift-jis decoder.
 
 - Patch #1478788 (modified version): The functional extension module has
diff --git a/Modules/binascii.c b/Modules/binascii.c
index 71a962452ec..3b2c8b254cd 100644
--- a/Modules/binascii.c
+++ b/Modules/binascii.c
@@ -909,7 +909,7 @@ binascii_hexlify(PyObject *self, PyObject *args)
 	char* retbuf;
 	Py_ssize_t i, j;
 
-	if (!PyArg_ParseTuple(args, "t#:b2a_hex", &argbuf, &arglen))
+	if (!PyArg_ParseTuple(args, "s#:b2a_hex", &argbuf, &arglen))
 		return NULL;
 
 	retval = PyString_FromStringAndSize(NULL, arglen*2);