diff --git a/HISTORY.md b/HISTORY.md
index 3f4d5d9d..0ca75332 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,3 +1,10 @@
+v0.4.1 (2014-7-7)
+-----------
+* Add SERVICE_NAME in loader
+* Throw error back when skynet.error
+* Add skynet.task
+* Bugfix for last version (harbor service bugs)
+
 v0.4.0 (2014-6-30)
 -----------
 * Optimize redis driver `compose_message`.
diff --git a/examples/simplemonitor.lua b/examples/simplemonitor.lua
index 1528bb50..ec294d21 100644
--- a/examples/simplemonitor.lua
+++ b/examples/simplemonitor.lua
@@ -12,7 +12,7 @@ skynet.register_protocol {
 		local w = service_map[address]
 		if w then
 			for watcher in pairs(w) do
-				skynet.redirect(watcher, address, "error", "")
+				skynet.redirect(watcher, address, "error", 0, "")
 			end
 			service_map[address] = false
 		end
diff --git a/lualib/loader.lua b/lualib/loader.lua
index 05224b92..1c4ee58a 100644
--- a/lualib/loader.lua
+++ b/lualib/loader.lua
@@ -3,11 +3,13 @@ for word in string.gmatch(..., "%S+") do
 	table.insert(args, word)
 end
 
+SERVICE_NAME = args[1]
+
 local main, pattern
 
 local err = {}
 for pat in string.gmatch(LUA_SERVICE, "([^;]+);*") do
-	local filename = string.gsub(pat, "?", args[1])
+	local filename = string.gsub(pat, "?", SERVICE_NAME)
 	local f, msg = loadfile(filename)
 	if not f then
 		table.insert(err, msg)
diff --git a/lualib/skynet.lua b/lualib/skynet.lua
index 2019f530..f9d934c3 100644
--- a/lualib/skynet.lua
+++ b/lualib/skynet.lua
@@ -253,6 +253,13 @@ end
 
 function skynet.exit()
 	skynet.send(".launcher","lua","REMOVE",skynet.self())
+	for co, session in pairs(session_coroutine_id) do
+		local address = session_coroutine_address[co]
+		local self = skynet.self()
+		if session~=0 and address then
+			skynet.redirect(self, address, "error", session, "")
+		end
+	end
 	c.command("EXIT")
 end
 
@@ -569,12 +576,24 @@ function skynet.monitor(service, query)
 	end
 	assert(monitor, "Monitor launch failed")
 	c.command("MONITOR", string.format(":%08x", monitor))
+	return monitor
 end
 
 function skynet.mqlen()
 	return tonumber(c.command "MQLEN")
 end
 
+function skynet.task(ret)
+	local t = 0
+	for session,co in pairs(session_id_coroutine) do
+		if ret then
+			ret[session] = debug.traceback(co)
+		end
+		t = t + 1
+	end
+	return t
+end
+
 -- Inject internal debug framework
 local debug = require "skynet.debug"
 debug(skynet)
diff --git a/lualib/skynet/debug.lua b/lualib/skynet/debug.lua
index 807ee2ae..c8f51f0b 100644
--- a/lualib/skynet/debug.lua
+++ b/lualib/skynet/debug.lua
@@ -21,9 +21,16 @@ end
 function dbgcmd.STAT()
 	local stat = {}
 	stat.mqlen = skynet.mqlen()
+	stat.task = skynet.task()
 	skynet.ret(skynet.pack(stat))
 end
 
+function dbgcmd.TASK()
+	local task = {}
+	skynet.task(task)
+	skynet.ret(skynet.pack(task))
+end
+
 function dbgcmd.INFO()
 	if internal_info_func then
 		skynet.ret(skynet.pack(internal_info_func()))
diff --git a/service-src/service_harbor.c b/service-src/service_harbor.c
index f7a88f2b..fbb6406d 100644
--- a/service-src/service_harbor.c
+++ b/service-src/service_harbor.c
@@ -262,7 +262,8 @@ harbor_release(struct harbor *h) {
 		struct slave *s = &h->s[i];
 		if (s->fd && s->status != STATUS_DOWN) {
 			close_harbor(h,i);
-			report_harbor_down(h,i);
+			// don't call report_harbor_down.
+			// never call skynet_send during module exit, because of dead lock
 		}
 	}
 	hash_delete(h->map);
@@ -509,6 +510,9 @@ remote_send_handle(struct harbor *h, uint32_t source, uint32_t destination, int
 			skynet_send(context, destination, source, PTYPE_ERROR, 0 , NULL, 0);
 			skynet_error(context, "Drop message to harbor %d from %x to %x (session = %d, msgsz = %d)",harbor_id, source, destination,session,(int)sz);
 		} else {
+			if (s->queue == NULL) {
+				s->queue = new_queue();
+			}
 			struct remote_message_header header;
 			header.source = source;
 			header.destination = type << HANDLE_REMOTE_SHIFT;
diff --git a/service/debug_console.lua b/service/debug_console.lua
index b15c3889..a587f69d 100644
--- a/service/debug_console.lua
+++ b/service/debug_console.lua
@@ -113,6 +113,7 @@ function COMMAND.help()
 		snax = "lanuch a new snax service",
 		clearcache = "clear lua code cache",
 		service = "List unique service",
+		task = "task address : show service task detail",
 	}
 end
 
diff --git a/service/launcher.lua b/service/launcher.lua
index b80eadc9..5c1c1a8b 100644
--- a/service/launcher.lua
+++ b/service/launcher.lua
@@ -38,6 +38,16 @@ function command.INFO(_, _, handle)
 	end
 end
 
+function command.TASK(_, _, handle)
+	handle = handle_to_address(handle)
+	if services[handle] == nil then
+		return
+	else
+		local result = skynet.call(handle,"debug","TASK")
+		return result
+	end
+end
+
 function command.KILL(_, _, handle)
 	handle = handle_to_address(handle)
 	skynet.kill(handle)
diff --git a/test/testdeadcall.lua b/test/testdeadcall.lua
index d348a411..c5d67b8c 100644
--- a/test/testdeadcall.lua
+++ b/test/testdeadcall.lua
@@ -14,7 +14,7 @@ end)
 else
 
 	skynet.start(function()
-		local test = skynet.newservice("testdeadcall", "test")	-- launch self in test mode
+		local test = skynet.newservice(SERVICE_NAME, "test")	-- launch self in test mode
 
 		print(pcall(function()
 			skynet.send(test,"lua", "hello world")
diff --git a/test/testmulticast.lua b/test/testmulticast.lua
index 88f79ccb..8f084abf 100644
--- a/test/testmulticast.lua
+++ b/test/testmulticast.lua
@@ -27,7 +27,7 @@ skynet.start(function()
 	local channel = mc.new()
 	print("New channel", channel)
 	for i=1,10 do
-		local sub = skynet.newservice("testmulticast", "sub")
+		local sub = skynet.newservice(SERVICE_NAME, "sub")
 		skynet.call(sub, "lua", "init", channel.channel)
 	end