diff --git a/mitogen/core.py b/mitogen/core.py
index 4f5e15be..7273f3d0 100644
--- a/mitogen/core.py
+++ b/mitogen/core.py
@@ -236,10 +236,15 @@ class Secret(UnicodeType):
 
 
 class Kwargs(dict):
-    """A serializable dict subclass that indicates the contained keys should be
-    be coerced to Unicode on Python 3 as required. Python 2 produces keyword
-    argument dicts whose keys are bytestrings, requiring a helper to ensure
-    compatibility with Python 3."""
+    """
+    A serializable dict subclass that indicates the contained keys should be be
+    coerced to Unicode on Python 3 and to bytes on Python<2.6.
+
+    Python 2 produces keyword argument dicts whose keys are bytestrings,
+    requiring a helper to ensure compatibility with Python 3, whereas Python 3
+    produces keyword argument dicts whose keys are unicode, requiring a helper
+    to ensure compatibility with Python 2.4 and 2.5.
+    """
     if PY3:
         def __init__(self, dct):
             for k, v in dct.items():
@@ -247,6 +252,13 @@ class Kwargs(dict):
                     self[k.decode()] = v
                 else:
                     self[k] = v
+    elif sys.version_info < (2, 6):
+        def __init__(self, dct):
+            for k, v in dct.iteritems():
+                if type(k) is unicode:
+                    self[k.encode()] = v
+                else:
+                    self[k] = v
 
     def __repr__(self):
         return 'Kwargs(%s)' % (dict.__repr__(self),)
diff --git a/mitogen/parent.py b/mitogen/parent.py
index 6e902bdd..6305aca8 100644
--- a/mitogen/parent.py
+++ b/mitogen/parent.py
@@ -1935,8 +1935,10 @@ class Router(mitogen.core.Router):
 
         via = kwargs.pop(u'via', None)
         if via is not None:
-            return self.proxy_connect(via, method_name, name=name, **kwargs)
-        return self._connect(klass, name=name, **kwargs)
+            return self.proxy_connect(via, method_name, name=name,
+                                      **mitogen.core.Kwargs(kwargs))
+        return self._connect(klass, name=name,
+                             **mitogen.core.Kwargs(kwargs))
 
     def proxy_connect(self, via_context, method_name, name=None, **kwargs):
         resp = via_context.call(_proxy_connect,
diff --git a/tests/types_test.py b/tests/types_test.py
index bd243949..9166f577 100644
--- a/tests/types_test.py
+++ b/tests/types_test.py
@@ -1,4 +1,6 @@
 
+import sys
+
 try:
     from io import StringIO
     from io import BytesIO
@@ -88,7 +90,14 @@ class KwargsTest(testlib.TestCase):
         self.assertTrue(type(dct) is dict)
         self.assertEquals({}, dct)
 
-    @unittest2.skipIf(condition=lambda: not mitogen.core.PY3,
+    @unittest2.skipIf(condition=(sys.version_info >= (2, 6)),
+                      reason='py<2.6 only')
+    def test_bytes_conversion(self):
+        kw = self.klass({u'key': 123})
+        self.assertEquals({'key': 123}, kw)
+        self.assertEquals("Kwargs({'key': 123})", repr(kw))
+
+    @unittest2.skipIf(condition=not mitogen.core.PY3,
                       reason='py3 only')
     def test_unicode_conversion(self):
         kw = self.klass({mitogen.core.b('key'): 123})