Index: Lib/test/test_datetime.py
===================================================================
--- Lib/test/test_datetime.py	(revision 3405)
+++ Lib/test/test_datetime.py	(working copy)
@@ -2931,16 +2931,6 @@
                 ]
     return unittest.TestSuite(allsuites)
 
-# Jython transition 2.3
-# pickling doesn't work on any of the types in datetime
-# http://jython.org/bugs/1758312
-del TestDate.test_pickling
-del TestDateTime.test_pickling
-del TestDateTime.test_more_pickling
-del TestTime.test_pickling
-del TestDateTimeTZ.test_pickling
-del TestTimeTZ.test_pickling
-
 def test_main():
     #import gc
     import sys
Index: Lib/datetime.py
===================================================================
--- Lib/datetime.py	(revision 3405)
+++ Lib/datetime.py	(working copy)
@@ -232,7 +232,7 @@
 
 # Just raise TypeError if the arg isn't None or a string.
 def _check_tzname(name):
-    if name is not None and not isinstance(name, str):
+    if name is not None and not isinstance(name, basestring):
         raise TypeError("tzinfo.tzname() must return None or string, "
                         "not '%s'" % type(name))
 
@@ -725,7 +725,7 @@
 
         year, month, day (required, base 1)
         """
-        if isinstance(year, str):
+        if isinstance(year, basestring):
             # Pickle support
             self = object.__new__(cls)
             self.__setstate((year,))
@@ -1088,7 +1088,7 @@
         tzinfo (default to None)
         """
         self = object.__new__(cls)
-        if isinstance(hour, str):
+        if isinstance(hour, basestring):
             # Pickle support
             self.__setstate((hour, minute or None))
             return self
@@ -1357,7 +1357,7 @@
 
     def __new__(cls, year, month=None, day=None, hour=0, minute=0, second=0,
                 microsecond=0, tzinfo=None):
-        if isinstance(year, str):
+        if isinstance(year, basestring):
             # Pickle support
             self = date.__new__(cls, year[:4])
             self.__setstate((year, month))