Guido pointed out that all names in the sys module have no underscore,
diff --git a/Doc/lib/libsys.tex b/Doc/lib/libsys.tex
index 5cc833d..bbea623 100644
--- a/Doc/lib/libsys.tex
+++ b/Doc/lib/libsys.tex
@@ -20,7 +20,7 @@
   \code{argv} has zero length.
 \end{datadesc}
 
-\begin{datadesc}{byte_order}
+\begin{datadesc}{byteorder}
   An indicator of the native byte order.  This will have the value
   \code{'big'} on big-endian (most-signigicant byte first) platforms,
   and \code{'little'} on little-endian (least-significant byte first)
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 99a6ff7..3026b66 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -461,14 +461,15 @@
 		/* Assumes that longs are at least 2 bytes long.
 		   Should be safe! */
 		unsigned long number = 1;
+		char *value;
 
 		s = (char *) &number;
 		if (s[0] == 0)
-			PyDict_SetItemString(sysdict, "byte_order",
-					     PyString_FromString("big"));
+			value = "big";
 		else
-			PyDict_SetItemString(sysdict, "byte_order",
-					     PyString_FromString("little"));
+			value = "little";
+		PyDict_SetItemString(sysdict, "byteorder",
+				     PyString_FromString(value));
 	}
 #ifdef MS_COREDLL
 	PyDict_SetItemString(sysdict, "dllhandle",