polkitd crashed while user was entering password to authenticate. PK version is 0.95 (Ubuntu 10.04).

Reported at https://bugs.launchpad.net/ubuntu/+source/policykit-1/+bug/509651
(There are about 10 duplicate reports.)

Trace:
#0  0x00183790 in __strlen_sse2 () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#1  0x00c0fd4d in _dbus_marshal_write_basic (str=0x9355290, insert_at=54, 
    type=115, value=0xbfce05dc, byte_order=108, pos_after=0xbfce04e0)
    at dbus-marshal-basic.c:775
No locals.
#2  0x00bfb9f3 in _dbus_type_writer_write_basic (writer=0xbfce04d0, type=115, 
    value=0xbfce05dc) at dbus-marshal-recursive.c:1588
	retval = <value optimized out>
#3  0x00c0093e in dbus_message_iter_append_basic (iter=0xbfce04c8, type=115, 
    value=0xbfce05dc) at dbus-message.c:2284
	ret = <value optimized out>
	__FUNCTION__ = "dbus_message_iter_append_basic"
#4  0x00aa05ca in egg_dbus_append_value_to_iter (iter=<value optimized out>, 
    signature=0xbfce05dc "", value=0xbfce0704, error=0xbfce082c)
    at eggdbusmessage.c:2819
	val = {g_type = 0, data = {{v_int = 0, v_uint = 0, v_long = 0, 
      v_ulong = 0, v_int64 = 0, v_uint64 = 0, v_float = 0, v_double = 0, 
      v_pointer = 0x0}, {v_int = 0, v_uint = 0, v_long = 0, v_ulong = 0, 
      v_int64 = 0, v_uint64 = 0, v_float = 0, v_double = 0, v_pointer = 0x0}}}
	dict_iter = {dummy1 = 0x9355250, dummy2 = 0x4e00000, dummy3 = 222572, 
  dummy4 = 154489168, dummy5 = 6, dummy6 = 154489488, dummy7 = 54, 
  dummy8 = 16, dummy9 = 8, dummy10 = 4, dummy11 = 154489488, pad1 = 0, 
  pad2 = 16, pad3 = 0xc1eff4}
	array_iter = {dummy1 = 0x9355250, dummy2 = 0x3e00000, 
  dummy3 = 221548, dummy4 = 154489168, dummy5 = 4, dummy6 = 154489488, 
  dummy7 = 16, dummy8 = 16, dummy9 = 8, dummy10 = 4, dummy11 = 154274996, 
  pad1 = 4505588, pad2 = 154373600, pad3 = 0x9374018}
	hash_iter = {dummy1 = 0x9339f50, dummy2 = 0x41a3f2, 
  dummy3 = 0x9338de4, dummy4 = 1, dummy5 = -1077017224, dummy6 = 0x1}
	hash_key = (gpointer) 0x93556c0
	hash_value = (gpointer) 0x0
	hash_table = <value optimized out>
	value_signature = 0x9336520 "s"
	ret = <value optimized out>
	__PRETTY_FUNCTION__ = "egg_dbus_append_value_to_iter"
#5  0x00aa00c0 in egg_dbus_append_value_to_iter (iter=<value optimized out>, 
    signature=<value optimized out>, value=0xbfce07cc, error=0xbfce082c)
    at eggdbusmessage.c:3002
	val = {g_type = 154356168, data = {{v_int = 154373600, 
      v_uint = 154373600, v_long = 154373600, v_ulong = 154373600, 
      v_int64 = 154373600, v_uint64 = 154373600, v_float = 2.16130506e-33, 
      v_double = 7.6270692384838258e-316, v_pointer = 0x9338de0}, {v_int = 0, 
      v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, 
      v_float = 0, v_double = 0, v_pointer = 0x0}}}
	sig_for_elem = <value optimized out>
	struct_iter = {dummy1 = 0x9355250, dummy2 = 0x2e00000, 
  dummy3 = 160364, dummy4 = 154489168, dummy5 = 8, dummy6 = 154489488, 
  dummy7 = 8, dummy8 = 0, dummy9 = 0, dummy10 = 0, dummy11 = 4505588, 
  pad1 = 1, pad2 = -1077016696, pad3 = 0x356c84}
	structure = (EggDBusStructure *) 0x93566c0
	n = 2
	num_elems = 3
	ret = <value optimized out>
	__PRETTY_FUNCTION__ = "egg_dbus_append_value_to_iter"
#6  0x00aa1b52 in egg_dbus_message_append_structure (message=0x933ab98, 
    structure=0x93566c0, error=0xbfce082c) at eggdbusmessage.c:1182
	val = {g_type = 154390712, data = {{v_int = 154494656, 
      v_uint = 154494656, v_long = 154494656, v_ulong = 154494656, 
      v_int64 = 154494656, v_uint64 = 154494656, v_float = 2.18353953e-33, 
      v_double = 7.6330501995661215e-316, v_pointer = 0x93566c0}, {v_int = 0, 
      v_uint = 0, v_long = 0, v_ulong = 0, v_int64 = 0, v_uint64 = 0, 
      v_float = 0, v_double = 0, v_pointer = 0x0}}}
#7  0x009201d1 in _polkit_authority_handle_check_authorization_finish (
    method_invocation=0x93ad860, _out_result=0x93566c0)
    at _polkitauthority.c:3213
	error = (GError *) 0x0
	reply = (EggDBusMessage *) 0x933ab98
	__PRETTY_FUNCTION__ = "_polkit_authority_handle_check_authorization_finish"
#8  0x00913a01 in check_auth_cb (source_object=0x933f8f0, res=0x933ef58, 
    user_data=0x93ad860) at polkitbackendauthority.c:880
	real_result = (_PolkitAuthorizationResult *) 0x93566c0
	method_invocation = (EggDBusMethodInvocation *) 0x93ad860
	result = (PolkitAuthorizationResult *) 0x9355aa8
	error = (GError *) 0x0
#9  0x0049e890 in g_simple_async_result_complete ()
   from /usr/lib/libgio-2.0.so.0
No symbol table info available.
#10 0x00915246 in check_authorization_challenge_cb (agent=0x93a4600, 
    subject=0x93a1e90, user_of_subject=0x93a1d70, authority=0x933f8f0, 
    action_id=0x93ae940 "org.gnome.displaymanager.settings.write", 
    implicit_authorization=POLKIT_IMPLICIT_AUTHORIZATION_ADMINISTRATOR_AUTHENTICATION_REQUIRED_RETAINED, authentication_success=1, user_data=0x933ef58)
    at polkitbackendinteractiveauthority.c:412
	simple = (GSimpleAsyncResult *) 0x933ef58
	result = <value optimized out>
	subject_str = (gchar *) 0x9138f0 "U\211�S���\201��01"
#11 0x00915075 in authentication_agent_begin_callback (
    source_object=0x9373bb8, res=0x932db00, user_data=0x93ae898)
    at polkitbackendinteractiveauthority.c:1302
	error = (GError *) 0x0
	gained_authorization = 1
#12 0x0049e890 in g_simple_async_result_complete ()
   from /usr/lib/libgio-2.0.so.0
No symbol table info available.
#13 0x0091e4fc in generic_async_callback (source_object=0x932d6f0, 
    res=0x933ee40, user_data=0x932db00) at _polkitauthenticationagent.c:293
	simple = (GSimpleAsyncResult *) 0x932db00
	reply = <value optimized out>
	error = (GError *) 0x0
#14 0x0049e890 in g_simple_async_result_complete ()
   from /usr/lib/libgio-2.0.so.0
No symbol table info available.
#15 0x00a9a9c8 in egg_dbus_connection_send_message_with_reply_cb (
    pending_call=0x914fb0, simple=0x933ee40) at eggdbusconnection.c:2404
	dreply = (DBusMessage *) 0x9326000
	derror = {name = 0x0, message = 0x0, dummy1 = 1, dummy2 = 0, 
  dummy3 = 1, dummy4 = 0, dummy5 = 1, padding1 = 0xc1eff4}
#16 0x00c04791 in _dbus_pending_call_complete (pending=0x93aea18)
    at dbus-pending-call.c:196
	user_data = (void *) 0x0
#17 0x00bf43f6 in complete_pending_call_and_unlock (connection=0x9331290, 
    pending=0x93aea18, message=0x9326000) at dbus-connection.c:2227
No locals.
#18 0x00bf69b2 in dbus_connection_dispatch (connection=0x9331290)
    at dbus-connection.c:4390
	message = <value optimized out>
	link = <value optimized out>
	filter_list_copy = <value optimized out>
	message_link = <value optimized out>
	result = <value optimized out>
	status = <value optimized out>
	__FUNCTION__ = "dbus_connection_dispatch"
#19 0x005f77fd in message_queue_dispatch (source=0x9338788, callback=0, 
    user_data=0x0) at dbus-gmain.c:101
	connection = (DBusConnection *) 0x9331290
#20 0x00331fe8 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
No symbol table info available.
#21 0x00335890 in ?? () from /lib/libglib-2.0.so.0
No symbol table info available.
#22 0x00335cff in g_main_loop_run () from /lib/libglib-2.0.so.0
No symbol table info available.
#23 0x0804882a in main (argc=1, argv=0xbfce0e34) at main.c:59
	ret = 0
	error = (GError *) 0x0
	loop = <value optimized out>
	authority = (PolkitBackendAuthority *) 0x933f8f0