diff --git a/IPython/core/formatters.py b/IPython/core/formatters.py
index 85b1b22..af4bf4d 100644
--- a/IPython/core/formatters.py
+++ b/IPython/core/formatters.py
@@ -432,8 +432,11 @@ class PlainTextFormatter(BaseFormatter):
         else:
             # This uses use StringIO, as cStringIO doesn't handle unicode.
             stream = StringIO()
+            # self.newline.encode() is a quick fix for issue gh-597. We need to
+            # ensure that stream does not get a mix of unicode and bytestrings,
+            # or it will cause trouble.
             printer = pretty.RepresentationPrinter(stream, self.verbose,
-                self.max_width, self.newline,
+                self.max_width, self.newline.encode(),
                 singleton_pprinters=self.singleton_printers,
                 type_pprinters=self.type_printers,
                 deferred_pprinters=self.deferred_printers)
diff --git a/IPython/core/tests/test_interactiveshell.py b/IPython/core/tests/test_interactiveshell.py
index b4e5fcf..29dc92d 100644
--- a/IPython/core/tests/test_interactiveshell.py
+++ b/IPython/core/tests/test_interactiveshell.py
@@ -112,5 +112,13 @@ class InteractiveShellTestCase(unittest.TestCase):
         ip = get_ipython()
         ip.run_cell('!(true)\n', False)
         ip.run_cell('!(true)\n\n\n', False)
-
-
+    
+    def test_gh_597(self):
+        """Pretty-printing lists of objects with non-ascii reprs may cause
+        problems."""
+        class Spam(object):
+          def __repr__(self):
+            return "\xe9"*50
+        import IPython.core.formatters
+        f = IPython.core.formatters.PlainTextFormatter()
+        f([Spam(),Spam()])