diff --git a/Lib/test/string_tests.py b/Lib/test/string_tests.py
index aab98c2..473a2e7 100644
--- a/Lib/test/string_tests.py
+++ b/Lib/test/string_tests.py
@@ -376,6 +376,153 @@
         self.checkraises(TypeError, 'hello', 'swapcase', 42)
 
     def test_replace(self):
+        EQ = self.checkequal
+
+        # Operations on the empty string
+        EQ("", "", "replace", "", "")
+        EQ("A", "", "replace", "", "A")
+        EQ("", "", "replace", "A", "")
+        EQ("", "", "replace", "A", "A")
+        EQ("", "", "replace", "", "", 100)
+        EQ("", "", "replace", "", "", sys.maxint)
+
+        # interleave (from=="", 'to' gets inserted everywhere)
+        EQ("A", "A", "replace", "", "")
+        EQ("*A*", "A", "replace", "", "*")
+        EQ("*1A*1", "A", "replace", "", "*1")
+        EQ("*-#A*-#", "A", "replace", "", "*-#")
+        EQ("*-A*-A*-", "AA", "replace", "", "*-")
+        EQ("*-A*-A*-", "AA", "replace", "", "*-", -1)
+        EQ("*-A*-A*-", "AA", "replace", "", "*-", sys.maxint)
+        EQ("*-A*-A*-", "AA", "replace", "", "*-", 4)
+        EQ("*-A*-A*-", "AA", "replace", "", "*-", 3)
+        EQ("*-A*-A", "AA", "replace", "", "*-", 2)
+        EQ("*-AA", "AA", "replace", "", "*-", 1)
+        EQ("AA", "AA", "replace", "", "*-", 0)
+
+        # single character deletion (from=="A", to=="")
+        EQ("", "A", "replace", "A", "")
+        EQ("", "AAA", "replace", "A", "")
+        EQ("", "AAA", "replace", "A", "", -1)
+        EQ("", "AAA", "replace", "A", "", sys.maxint)
+        EQ("", "AAA", "replace", "A", "", 4)
+        EQ("", "AAA", "replace", "A", "", 3)
+        EQ("A", "AAA", "replace", "A", "", 2)
+        EQ("AA", "AAA", "replace", "A", "", 1)
+        EQ("AAA", "AAA", "replace", "A", "", 0)
+        EQ("", "AAAAAAAAAA", "replace", "A", "")
+        EQ("BCD", "ABACADA", "replace", "A", "")
+        EQ("BCD", "ABACADA", "replace", "A", "", -1)
+        EQ("BCD", "ABACADA", "replace", "A", "", sys.maxint)
+        EQ("BCD", "ABACADA", "replace", "A", "", 5)
+        EQ("BCD", "ABACADA", "replace", "A", "", 4)
+        EQ("BCDA", "ABACADA", "replace", "A", "", 3)
+        EQ("BCADA", "ABACADA", "replace", "A", "", 2)
+        EQ("BACADA", "ABACADA", "replace", "A", "", 1)
+        EQ("ABACADA", "ABACADA", "replace", "A", "", 0)
+        EQ("BCD", "ABCAD", "replace", "A", "")
+        EQ("BCD", "ABCADAA", "replace", "A", "")
+        EQ("BCD", "BCD", "replace", "A", "")
+        EQ("*************", "*************", "replace", "A", "")
+        EQ("^A^", "^"+"A"*1000+"^", "replace", "A", "", 999)
+
+        # substring deletion (from=="the", to=="")
+        EQ("", "the", "replace", "the", "")
+        EQ("ater", "theater", "replace", "the", "")
+        EQ("", "thethe", "replace", "the", "")
+        EQ("", "thethethethe", "replace", "the", "")
+        EQ("aaaa", "theatheatheathea", "replace", "the", "")
+        EQ("that", "that", "replace", "the", "")
+        EQ("thaet", "thaet", "replace", "the", "")
+        EQ("here and re", "here and there", "replace", "the", "")
+        EQ("here and re and re", "here and there and there",
+           "replace", "the", "", sys.maxint)
+        EQ("here and re and re", "here and there and there",
+           "replace", "the", "", -1)
+        EQ("here and re and re", "here and there and there",
+           "replace", "the", "", 3)
+        EQ("here and re and re", "here and there and there",
+           "replace", "the", "", 2)
+        EQ("here and re and there", "here and there and there",
+           "replace", "the", "", 1)
+        EQ("here and there and there", "here and there and there",
+           "replace", "the", "", 0)
+        EQ("here and re and re", "here and there and there", "replace", "the", "")
+
+        EQ("abc", "abc", "replace", "the", "")
+        EQ("abcdefg", "abcdefg", "replace", "the", "")
+
+        # substring deletion (from=="bob", to=="")
+        EQ("bob", "bbobob", "replace", "bob", "")
+        EQ("bobXbob", "bbobobXbbobob", "replace", "bob", "")
+        EQ("aaaaaaa", "aaaaaaabob", "replace", "bob", "")
+        EQ("aaaaaaa", "aaaaaaa", "replace", "bob", "")
+        
+        # single character replace in place (len(from)==len(to)==1)
+        EQ("Who goes there?", "Who goes there?", "replace", "o", "o")
+        EQ("WhO gOes there?", "Who goes there?", "replace", "o", "O")
+        EQ("WhO gOes there?", "Who goes there?", "replace", "o", "O", sys.maxint)
+        EQ("WhO gOes there?", "Who goes there?", "replace", "o", "O", -1)
+        EQ("WhO gOes there?", "Who goes there?", "replace", "o", "O", 3)
+        EQ("WhO gOes there?", "Who goes there?", "replace", "o", "O", 2)
+        EQ("WhO goes there?", "Who goes there?", "replace", "o", "O", 1)
+        EQ("Who goes there?", "Who goes there?", "replace", "o", "O", 0)
+
+        EQ("Who goes there?", "Who goes there?", "replace", "a", "q")
+        EQ("who goes there?", "Who goes there?", "replace", "W", "w")
+        EQ("wwho goes there?ww", "WWho goes there?WW", "replace", "W", "w")
+        EQ("Who goes there!", "Who goes there?", "replace", "?", "!")
+        EQ("Who goes there!!", "Who goes there??", "replace", "?", "!")
+
+        EQ("Who goes there?", "Who goes there?", "replace", ".", "!")
+        
+        # substring replace in place (len(from)==len(to) > 1)
+        EQ("Th** ** a t**sue", "This is a tissue", "replace", "is", "**")
+        EQ("Th** ** a t**sue", "This is a tissue", "replace", "is", "**", sys.maxint)
+        EQ("Th** ** a t**sue", "This is a tissue", "replace", "is", "**", -1)
+        EQ("Th** ** a t**sue", "This is a tissue", "replace", "is", "**", 4)
+        EQ("Th** ** a t**sue", "This is a tissue", "replace", "is", "**", 3)
+        EQ("Th** ** a tissue", "This is a tissue", "replace", "is", "**", 2)
+        EQ("Th** is a tissue", "This is a tissue", "replace", "is", "**", 1)
+        EQ("This is a tissue", "This is a tissue", "replace", "is", "**", 0)
+        EQ("cobob", "bobob", "replace", "bob", "cob")
+        EQ("cobobXcobocob", "bobobXbobobob", "replace", "bob", "cob")
+        EQ("bobob", "bobob", "replace", "bot", "bot")
+
+        # replace single character (len(from)==1, len(to)>1)
+        EQ("ReyKKjaviKK", "Reykjavik", "replace", "k", "KK")
+        EQ("ReyKKjaviKK", "Reykjavik", "replace", "k", "KK", -1)
+        EQ("ReyKKjaviKK", "Reykjavik", "replace", "k", "KK", sys.maxint)
+        EQ("ReyKKjaviKK", "Reykjavik", "replace", "k", "KK", 2)
+        EQ("ReyKKjavik", "Reykjavik", "replace", "k", "KK", 1)
+        EQ("Reykjavik", "Reykjavik", "replace", "k", "KK", 0)
+        EQ("A----B----C----", "A.B.C.", "replace", ".", "----")
+
+        EQ("Reykjavik", "Reykjavik", "replace", "q", "KK")
+
+        # replace substring (len(from)>1, len(to)!=len(from))
+        EQ("ham, ham, eggs and ham", "spam, spam, eggs and spam",
+           "replace", "spam", "ham")
+        EQ("ham, ham, eggs and ham", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", sys.maxint)
+        EQ("ham, ham, eggs and ham", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", -1)
+        EQ("ham, ham, eggs and ham", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", 4)
+        EQ("ham, ham, eggs and ham", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", 3)
+        EQ("ham, ham, eggs and spam", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", 2)
+        EQ("ham, spam, eggs and spam", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", 1)
+        EQ("spam, spam, eggs and spam", "spam, spam, eggs and spam",
+           "replace", "spam", "ham", 0)
+
+        EQ("bobob", "bobobob", "replace", "bobob", "bob")
+        EQ("bobobXbobob", "bobobobXbobobob", "replace", "bobob", "bob")
+        EQ("BOBOBOB", "BOBOBOB", "replace", "bob", "bobby")
+        
+        # 
         self.checkequal('one@two!three!', 'one!two!three!', 'replace', '!', '@', 1)
         self.checkequal('onetwothree', 'one!two!three!', 'replace', '!', '')
         self.checkequal('one@two@three!', 'one!two!three!', 'replace', '!', '@', 2)
@@ -403,6 +550,16 @@
         self.checkraises(TypeError, 'hello', 'replace', 42, 'h')
         self.checkraises(TypeError, 'hello', 'replace', 'h', 42)
 
+### Commented out until the underlying libraries are fixed
+##    def test_replace_overflow(self):
+##        # Check for overflow checking on 32 bit machines
+##        if sys.maxint != 2147483647:
+##            return
+##        A2_16 = "A" * (2**16)
+##        self.checkraises(OverflowError, A2_16, "replace", "", A2_16)
+##        self.checkraises(OverflowError, A2_16, "replace", "A", A2_16)
+##        self.checkraises(OverflowError, A2_16, "replace", "AA", A2_16+A2_16)
+
     def test_zfill(self):
         self.checkequal('123', '123', 'zfill', 2)
         self.checkequal('123', '123', 'zfill', 3)