Renamed _testXXX to _testcapiXXX.  Jack is my hero -- good call!
diff --git a/setup.py b/setup.py
index bd74ab4..4c42a65 100644
--- a/setup.py
+++ b/setup.py
@@ -176,7 +176,7 @@
         # access to the builtin codecs and codec registry
         exts.append( Extension('_codecs', ['_codecsmodule.c']) )
         # Python C API test module
-        exts.append( Extension('_test', ['_testmodule.c']) )
+        exts.append( Extension('_testcapi', ['_testcapimodule.c']) )
         # static Unicode character database
         exts.append( Extension('unicodedata', ['unicodedata.c']) )
         # access to ISO C locale support