A tentative fix for SF bug #503837 (Roeland Rengelink): type.__module__ problems (again?) This simply initializes the __module__ local in a class statement from the __name__ global. I'm not 100% sure that this is the correct fix, although it usually does the right thing. The problem is that if the class statement executes in a custom namespace, the __name__ global may be taken from __builtins__, in which case it would have the value __builtin__, or it may not exist at all (if the custom namespace also has a custom __builtins__), in which case the class statement will fail. Nevertheless, unless someone finds a better solution, this is a 2.2.1 bugfix too.

--- a/Python/compile.c	Tue Jan 15 20:36:14 2002 +0000
+++ b/Python/compile.c	Tue Jan 15 21:06:07 2002 +0000
@@ -3926,6 +3926,9 @@
 	/* classdef: 'class' NAME ['(' testlist ')'] ':' suite */
 	c->c_name = STR(CHILD(n, 1));
 	c->c_private = c->c_name;
+	/* Initialize local __module__ from global __name__ */
+	com_addop_name(c, LOAD_GLOBAL, "__name__");
+	com_addop_name(c, STORE_NAME, "__module__");
 	ch = CHILD(n, NCH(n)-1); /* The suite */
 	doc = get_docstring(c, ch);
 	if (doc != NULL) {