Use binary mode to open "wave" files.
diff --git a/Lib/test/test_wave.py b/Lib/test/test_wave.py
index a7a5e24..e2dc688 100644
--- a/Lib/test/test_wave.py
+++ b/Lib/test/test_wave.py
@@ -13,7 +13,7 @@
 
 testfile = tempfile.mktemp()
 
-f = wave.open(testfile, 'w')
+f = wave.open(testfile, 'wb')
 f.setnchannels(nchannels)
 f.setsampwidth(sampwidth)
 f.setframerate(framerate)
@@ -22,7 +22,7 @@
 f.writeframes(output)
 f.close()
 
-f = wave.open(testfile, 'r')
+f = wave.open(testfile, 'rb')
 check(nchannels == f.getnchannels(), "nchannels")
 check(sampwidth == f.getsampwidth(), "sampwidth")
 check(framerate == f.getframerate(), "framerate")