Index: errors.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Python/errors.c,v
retrieving revision 2.75
diff -u -r2.75 errors.c
--- errors.c	11 Dec 2002 14:04:59 -0000	2.75
+++ errors.c	15 Feb 2003 04:47:08 -0000
@@ -601,21 +601,26 @@
 }
 
 
+extern int PyImport_LockImport(int wait);
+extern void PyImport_UnlockImport(void);
+
 /* Function to issue a warning message; may raise an exception. */
 int
 PyErr_Warn(PyObject *category, char *message)
 {
 	PyObject *mod, *dict, *func = NULL;
+	int got_lock = PyImport_LockImport(0);
 
-	mod = PyImport_ImportModule("warnings");
-	if (mod != NULL) {
-		dict = PyModule_GetDict(mod);
-		func = PyDict_GetItemString(dict, "warn");
-		Py_DECREF(mod);
+	if (got_lock) {
+		mod = PyImport_ImportModule("warnings");
+		if (mod != NULL) {
+			dict = PyModule_GetDict(mod);
+			func = PyDict_GetItemString(dict, "warn");
+			Py_DECREF(mod);
+		}
 	}
 	if (func == NULL) {
 		PySys_WriteStderr("warning: %s\n", message);
-		return 0;
 	}
 	else {
 		PyObject *args, *res;
@@ -630,8 +635,10 @@
 		if (res == NULL)
 			return -1;
 		Py_DECREF(res);
-		return 0;
 	}
+	if (got_lock)
+		PyImport_UnlockImport();
+	return 0;
 }
 
 
Index: import.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Python/import.c,v
retrieving revision 2.218
diff -u -r2.218 import.c
--- import.c	12 Feb 2003 23:02:19 -0000	2.218
+++ import.c	15 Feb 2003 04:47:09 -0000
@@ -240,26 +240,42 @@
 static long import_lock_thread = -1;
 static int import_lock_level = 0;
 
-static void
-lock_import(void)
+static int
+do_lock_import(int wait)
 {
 	long me = PyThread_get_thread_ident();
 	if (me == -1)
-		return; /* Too bad */
+		return 0; /* Too bad */
 	if (import_lock == NULL)
 		import_lock = PyThread_allocate_lock();
 	if (import_lock_thread == me) {
 		import_lock_level++;
-		return;
+		return 1;
 	}
 	if (import_lock_thread != -1 || !PyThread_acquire_lock(import_lock, 0))
 	{
-		PyThreadState *tstate = PyEval_SaveThread();
-		PyThread_acquire_lock(import_lock, 1);
-		PyEval_RestoreThread(tstate);
+		if (!wait)
+			return 0;
+		else {
+			PyThreadState *tstate = PyEval_SaveThread();
+			PyThread_acquire_lock(import_lock, 1);
+			PyEval_RestoreThread(tstate);
+		}
 	}
 	import_lock_thread = me;
 	import_lock_level = 1;
+	return 1;
+}
+
+static void
+lock_import(void)
+{
+	do_lock_import(1);
+}
+
+int PyImport_LockImport(int wait)
+{
+	return do_lock_import(wait);
 }
 
 static int
@@ -283,7 +299,16 @@
 #define lock_import()
 #define unlock_import() 0
 
+int PyImport_LockImport(int)
+{
+	return 1;
+}
 #endif
+
+void PyImport_UnlockImport(void)
+{
+	unlock_import();
+}
 
 static PyObject *
 imp_lock_held(PyObject *self, PyObject *args)