diff -ru dbus-python.orig/dbus/_expat_introspect_parser.py dbus-python/dbus/_expat_introspect_parser.py
--- dbus-python.orig/dbus/_expat_introspect_parser.py	2011-03-02 10:59:21.000000000 +0800
+++ dbus-python/dbus/_expat_introspect_parser.py	2011-03-02 16:14:36.000000000 +0800
@@ -58,7 +58,11 @@
             if (not self.in_method and name == 'interface'):
                 self.in_iface = ''
             elif (self.in_method and name == 'method'):
-                self.map[self.in_iface + '.' + self.in_method] = self.sig
+                key = self.in_iface + '.' + self.in_method
+                if key not in self.map:
+                    self.map[key] = []
+                if self.sig not in self.map[key]:
+                    self.map[key].append(self.sig)
                 self.in_method = ''
                 self.sig = ''
 
@@ -67,12 +71,15 @@
     concatenation of all their 'in' parameters, and mapping
     ``interface.signal`` strings to the concatenation of all their
     parameters.
+    Keys are mapped to lists to handle the case of overloaded method
+    and signal names.
 
     Example output::
 
         {
-            'com.example.SignalEmitter.OneString': 's',
-            'com.example.MethodImplementor.OneInt32Argument': 'i',
+            'com.example.SignalEmitter.OneString': ['s'],
+            'com.example.MethodImplementor.OneInt32Argument': ['i'],
+            'com.example.MethodImplementor.Overloaded': ['s', 'i'],
         }
 
     :Parameters:
diff -ru dbus-python.orig/dbus/connection.py dbus-python/dbus/connection.py
--- dbus-python.orig/dbus/connection.py	2011-03-02 10:59:21.000000000 +0800
+++ dbus-python/dbus/connection.py	2011-03-02 16:28:59.000000000 +0800
@@ -557,19 +557,30 @@
         get_args_opts = {'utf8_strings': utf8_strings,
                          'byte_arrays': byte_arrays}
 
-        message = MethodCallMessage(destination=bus_name,
-                                    path=object_path,
-                                    interface=dbus_interface,
-                                    method=method)
-        # Add the arguments to the function
-        try:
-            message.append(signature=signature, *args)
-        except Exception, e:
+        if type(signature) is not list:
+            signature = [signature]
+
+        message = None
+        exception = None
+        for sig in signature:
+            this_message = MethodCallMessage(destination=bus_name,
+                                             path=object_path,
+                                             interface=dbus_interface,
+                                             method=method)
+            # Add the arguments to the function
+            try:
+                this_message.append(signature=sig, *args)
+            except Exception, e:
+                exception = e
+            else:
+                message = this_message
+
+        if message is None:
             logging.basicConfig()
             _logger.error('Unable to set arguments %r according to '
                           'signature %r: %s: %s',
                           args, signature, e.__class__, e)
-            raise
+            raise exception
 
         if reply_handler is None and error_handler is None:
             # we don't care what happens, so just send it
@@ -611,19 +622,30 @@
         get_args_opts = {'utf8_strings': utf8_strings,
                          'byte_arrays': byte_arrays}
 
-        message = MethodCallMessage(destination=bus_name,
-                                    path=object_path,
-                                    interface=dbus_interface,
-                                    method=method)
-        # Add the arguments to the function
-        try:
-            message.append(signature=signature, *args)
-        except Exception, e:
+        if type(signature) is not list:
+            signature = [signature]
+
+        message = None
+        exception = None
+        for sig in signature:
+            this_message = MethodCallMessage(destination=bus_name,
+                                             path=object_path,
+                                             interface=dbus_interface,
+                                             method=method)
+            # Add the arguments to the function
+            try:
+                this_message.append(signature=sig, *args)
+            except Exception, e:
+                exception = e
+            else:
+                message = this_message
+
+        if message is None:
             logging.basicConfig()
             _logger.error('Unable to set arguments %r according to '
                           'signature %r: %s: %s',
                           args, signature, e.__class__, e)
-            raise
+            raise exception
 
         # make a blocking call
         reply_message = self.send_message_with_reply_and_block(