diff --git a/Doc/ext/ext.tex b/Doc/ext/ext.tex
index 616695456a5..4bfff24cde1 100644
--- a/Doc/ext/ext.tex
+++ b/Doc/ext/ext.tex
@@ -702,10 +702,16 @@ Raises a \exception{TypeError} exception if the object is not a string
 object.  The C variable may also be declared as \ctype{PyObject *}.
 
 \item[\samp{(\var{items})} (tuple) {[\var{matching-items}]}]
-The object must be a Python tuple whose length is the number of format
-units in \var{items}.  The C arguments must correspond to the
-individual format units in \var{items}.  Format units for tuples may
-be nested.
+The object must be a Python sequence whose length is the number of
+format units in \var{items}.  The C arguments must correspond to the
+individual format units in \var{items}.  Format units for sequences
+may be nested.
+
+\strong{Note:} Prior to Python version 1.5.2, this format specifier
+only accepted a tuple containing the individual parameters, not an
+arbitrary sequence.  Code which previously caused a
+\exception{TypeError} to be raised here may now proceed without an
+exception.  This is not expected to be a problem for existing code.
 
 \end{description}