Index: src/org/python/core/PyString.java
===================================================================
--- src/org/python/core/PyString.java	(revision 3451)
+++ src/org/python/core/PyString.java	(working copy)
@@ -4048,6 +4048,11 @@
                 PyInteger val;
                 try {
                     val = (PyInteger)arg.__int__();
+		    if(val.getValue() < 0)
+			    throw Py.OverflowError("unsigned byte integer is less than minimum");
+		    else if(val.getValue() > 255)
+			    throw Py.OverflowError("unsigned byte integer is greater than maximum");
+
                 } catch(PyException e){
                     if(Py.matchException(e, Py.AttributeError)) {
                         throw Py.TypeError("%c requires int or char");
Index: Lib/test/string_tests.py
===================================================================
--- Lib/test/string_tests.py	(revision 3451)
+++ Lib/test/string_tests.py	(working copy)
@@ -546,12 +546,9 @@
         self.checkequal('$', "%c", '__mod__', 36)
         self.checkequal('10', "%d", '__mod__', 10)
         self.checkequal('\x7f', "%c", '__mod__', 0x7f)
-# Jython transition 2.3
-# values outside of the size of a single char aren't prohibited in formatting %c
-# http://jython.org/bugs/1768075
-#        for ordinal in (-100, 0x200000):
-            # unicode raises ValueError, str raises OverflowError
-#            self.checkraises((ValueError, OverflowError), '%c', '__mod__', ordinal)
+	
+       for ordinal in (-100, 0x200000):
+       	    self.checkraises((ValueError, OverflowError), '%c', '__mod__', ordinal)
 
         self.checkequal(' 42', '%3ld', '__mod__', 42)
         self.checkequal('0042.00', '%07.2f', '__mod__', 42)
Index: Lib/test/test_str.py
===================================================================
--- Lib/test/test_str.py	(revision 3451)
+++ Lib/test/test_str.py	(working copy)
@@ -16,10 +16,7 @@
 
     def test_formatting(self):
         string_tests.MixinStrUnicodeUserStringTest.test_formatting(self)
-# Jython transition 2.3
-# values outside of the size of a single char aren't prohibited in formatting %c
-# http://jython.org/bugs/1768075     
-#        self.assertRaises(OverflowError, '%c'.__mod__, 0x1234)
+        self.assertRaises(OverflowError, '%c'.__mod__, 0x1234)
 
 def test_main():
     test_support.run_unittest(StrTest)