diff --git a/doc/python.rst b/doc/python.rst
index 296a14f..594df51 100644
--- a/doc/python.rst
+++ b/doc/python.rst
@@ -258,8 +258,9 @@ Session Objects
     Puts back previously deferred DATA frame in the stream *stream_id*
     to the outbound queue.
 
-    The :py:class:`InvalidArgumentError` will be raised if the stream
-    does not exist or no deferred data exist.
+    This method returns ``True`` if it succeeds, or ``False``.  This
+    method will fail if the stream does not exist or no deferred data
+    exist.
 
 .. py:method:: Session.want_read()
 
diff --git a/python/spdylay.pyx b/python/spdylay.pyx
index a2807a0..3b694d8 100644
--- a/python/spdylay.pyx
+++ b/python/spdylay.pyx
@@ -778,9 +778,9 @@ cdef class Session:
         cpdef int rv
         rv = cspdylay.spdylay_session_resume_data(self._c_session, stream_id)
         if rv == 0:
-            return
+            return True
         elif rv == cspdylay.SPDYLAY_ERR_INVALID_ARGUMENT:
-            raise InvalidArgumentError(_strerror(rv))
+            return False
         elif rv == cspdylay.SPDYLAY_ERR_NOMEM:
             raise MemoryError()
 
diff --git a/python/spdylay_tests.py b/python/spdylay_tests.py
index 0ae3720..196e943 100644
--- a/python/spdylay_tests.py
+++ b/python/spdylay_tests.py
@@ -174,8 +174,7 @@ class SpdylayTests(unittest.TestCase):
         self.assertEqual(spdylay.GOAWAY_PROTOCOL_ERROR, frame.status_code)
 
     def test_resume_data(self):
-        with self.assertRaises(spdylay.InvalidArgumentError):
-            self.client_session.resume_data(1)
+        self.assertFalse(self.client_session.resume_data(1))
 
     def test_get_pri_lowest(self):
         self.assertEqual(7, self.client_session.get_pri_lowest())