Added the _sre module.  It is always on.
diff --git a/Modules/Setup.in b/Modules/Setup.in
index 4fd92a2..447e74b 100644
--- a/Modules/Setup.in
+++ b/Modules/Setup.in
@@ -93,6 +93,7 @@
 pcre pcremodule.c pypcre.c	# Regular expressions, Perl style (for re.py)
 posix posixmodule.c		# posix (UNIX) system calls
 signal signalmodule.c		# signal(2)
+_sre _sre.c			# Fredrik Lundh's new regular expressions
 
 # The SGI specific GL module: