When reading the file, option names were not passed through

self.optionxform(), which (in the default case) caused options spelled
with opper case letters in their name to be inaccessible.  Reported by
"Todd R. Palmer" <t2palmer@bellsouth.net> on
activepython@listserv1.ActiveState.com.

Lib/ConfigParser.py

@@ -440,7 +440,7 @@ def __read(self, fp, fpname):
                         # allow empty values
                         if optval == '""':
                             optval = ''
-                        cursect[optname] = optval
+                        cursect[self.optionxform(optname)] = optval
                     else:
                         # a non-fatal parsing error occurred.  set up the
                         # exception but keep going. the exception will be