Index: Lib/logging/__init__.py
===================================================================
--- Lib/logging/__init__.py	(revision 85007)
+++ Lib/logging/__init__.py	(working copy)
@@ -58,17 +58,6 @@
 except NameError:
     _unicode = False
 
-#
-# _srcfile is used when walking the stack to check when we've got the first
-# caller stack frame.
-#
-if hasattr(sys, 'frozen'): #support for py2exe
-    _srcfile = "logging%s__init__%s" % (os.sep, __file__[-4:])
-elif __file__[-4:].lower() in ['.pyc', '.pyo']:
-    _srcfile = __file__[:-4] + '.py'
-else:
-    _srcfile = __file__
-_srcfile = os.path.normcase(_srcfile)
 
 # next bit filched from 1.5.2's inspect.py
 def currentframe():
@@ -81,13 +70,6 @@
 if hasattr(sys, '_getframe'): currentframe = lambda: sys._getframe(3)
 # done filching
 
-# _srcfile is only used in conjunction with sys._getframe().
-# To provide compatibility with older versions of Python, set _srcfile
-# to None if _getframe() is not available; this value will prevent
-# findCaller() from being called.
-#if not hasattr(sys, "_getframe"):
-#    _srcfile = None
-
 #
 #_startTime is used as the base when calculating the relative time of events
 #
@@ -1199,20 +1181,14 @@
         Find the stack frame of the caller so that we can note the source
         file name, line number and function name.
         """
+        globs = globals()
         f = currentframe()
-        #On some versions of IronPython, currentframe() returns None if
-        #IronPython isn't run with -X:Frames.
-        if f is not None:
-            f = f.f_back
         rv = "(unknown file)", 0, "(unknown function)"
-        while hasattr(f, "f_code"):
+        while f is not None and f._globals is globs:
+            f = f.f_back
+        if f is not None:
             co = f.f_code
-            filename = os.path.normcase(co.co_filename)
-            if filename == _srcfile:
-                f = f.f_back
-                continue
-            rv = (filename, f.f_lineno, co.co_name)
-            break
+            rv = (os.co_filename, f.f_lineno, co.co_name)
         return rv
 
     def makeRecord(self, name, level, fn, lno, msg, args, exc_info, func=None, extra=None):
@@ -1233,16 +1209,7 @@
         Low-level logging routine which creates a LogRecord and then calls
         all the handlers of this logger to handle the record.
         """
-        if _srcfile:
-            #IronPython doesn't track Python frames, so findCaller throws an
-            #exception on some versions of IronPython. We trap it here so that
-            #IronPython can use logging.
-            try:
-                fn, lno, func = self.findCaller()
-            except ValueError:
-                fn, lno, func = "(unknown file)", 0, "(unknown function)"
-        else:
-            fn, lno, func = "(unknown file)", 0, "(unknown function)"
+        fn, lno, func = self.findCaller()
         if exc_info:
             if not isinstance(exc_info, tuple):
                 exc_info = sys.exc_info()