diff --git a/bsp/mini2440/startup.c b/bsp/mini2440/startup.c
index 4632ee9fcb1e25847dc29498a9c2e78866110cd7..466f6743d0784edd795d10371ab40c5120f2e81a 100644
--- a/bsp/mini2440/startup.c
+++ b/bsp/mini2440/startup.c
@@ -155,6 +155,8 @@ void rtthread_startup(void)
 #endif
 #endif
 
+	rt_system_timer_thread_init();
+
 	/* init idle thread */
 	rt_thread_idle_init();
 
diff --git a/include/rtdef.h b/include/rtdef.h
index 442f9ecd5db9f2f221bf0908de82dd77d38c152b..f6c1db41f6922877927eae0c5f1ba377be56f8e3 100644
--- a/include/rtdef.h
+++ b/include/rtdef.h
@@ -361,6 +361,10 @@ struct rt_thread
 };
 /*@}*/
 
+/* module clean types */
+#define RT_MODULE_FLAG_AUTO_CLEAN			0x01			/* auto clean	*/
+#define RT_MODULE_FLAG_MANUAL_CLEAN			0x02			/* manual clean */
+
 #ifdef RT_USING_MODULE
 struct rt_module
 {
diff --git a/src/idle.c b/src/idle.c
index 2354a21aac347ac2f59cf12532b86c117fbe2f1b..bebd0f7c4808a1d5882eaec839b374f9a1562f52 100644
--- a/src/idle.c
+++ b/src/idle.c
@@ -65,7 +65,9 @@ static void rt_thread_idle_entry(void* parameter)
 		if (!rt_list_isempty(&rt_thread_defunct))
 		{
 			rt_base_t lock;
-
+#ifdef RT_USING_MODULE
+			rt_module_t module;
+#endif
 			struct rt_thread* thread = rt_list_entry(rt_thread_defunct.next, struct rt_thread, tlist);
 
 			/* disable interrupt */
@@ -79,13 +81,33 @@ static void rt_thread_idle_entry(void* parameter)
 			/* release thread's stack */
 			rt_free(thread->stack_addr);
 
+			rt_kprintf("thread %s was deleted\n", thread->name);
+
 #ifdef RT_USING_MODULE
-			/* release thread point in module */
-			if(thread->module_parent != RT_NULL)
-				thread->module_parent->module_thread = RT_NULL;
-#endif
+			module = thread->module_parent;
+
 			/* delete thread object */
 			rt_object_delete((rt_object_t)thread);
+
+			if(module != RT_NULL)
+			{	
+				/* if the thread is module's main thread */
+				if(module->module_thread == thread)
+				{	
+					/* detach module's main thread */
+					module->module_thread = RT_NULL;
+				}
+
+				/* if sub thread list and main thread are null */
+				if((module->module_thread == RT_NULL) &&
+					rt_list_isempty(&module->module_object[RT_Object_Class_Thread].object_list) &&
+					(module->parent.flag & RT_MODULE_FLAG_AUTO_CLEAN))
+				{
+					/* unload module */
+					rt_module_unload(module);
+				}						
+			}	
+#endif
 		}
 #endif
 	}
diff --git a/src/module.c b/src/module.c
index af980541cba456b825c9da3fb0ccdef24216bb19..b29ee764d117120cd11c2f61e673b07ad642e61c 100644
--- a/src/module.c
+++ b/src/module.c
@@ -19,7 +19,7 @@
 #include "module.h"
 #include "kservice.h"
 
-/* #define RT_MODULE_DEBUG */
+/* #define RT_MODULE_DEBUG  */
 
 #define elf_module 	((Elf32_Ehdr *)module_ptr)
 #define shdr		((Elf32_Shdr *)((rt_uint8_t *)module_ptr + elf_module->e_shoff))
@@ -174,8 +174,8 @@ static void rt_module_init_object_container(struct rt_module* module)
 
 struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 {
-	rt_uint32_t index;
-	rt_uint32_t module_addr = 0, module_size = 0, rodata_addr = 0;
+	rt_uint32_t index, rodata_addr = 0, bss_addr = 0;
+	rt_uint32_t module_addr = 0, module_size = 0;
 	struct rt_module* module = RT_NULL;
 	rt_uint8_t *ptr, *strtab, *shstrab;
 
@@ -262,6 +262,7 @@ struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 		/* load bss section */
 		if (IS_NOPROG(shdr[index]) && IS_AW(shdr[index]))
 		{
+			bss_addr = (rt_uint32_t)ptr;
 			rt_memset(ptr, 0, shdr[index].sh_size);
 		}
 	}
@@ -298,7 +299,7 @@ struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 				{				
 					if(ELF_ST_TYPE(sym->st_info) == STT_SECTION)
 					{	
-						if (strncmp(shstrab + shdr[sym->st_shndx].sh_name, ELF_RODATA, 8) == 0)
+						if (rt_strncmp(shstrab + shdr[sym->st_shndx].sh_name, ELF_RODATA, 8) == 0)
 						{
 							/* relocate rodata section */
 							rt_module_arm_relocate(module, rel,
@@ -308,7 +309,7 @@ struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 						else if(strncmp(shstrab + shdr[sym->st_shndx].sh_name, ELF_BSS, 5) == 0)
 						{
 							/* relocate bss section */
-							rt_module_arm_relocate(module, rel, (Elf32_Addr)ptr, module_addr);
+							rt_module_arm_relocate(module, rel, (Elf32_Addr)bss_addr, module_addr);
 						}	
 					}
 					else if(ELF_ST_TYPE(sym->st_info) == STT_FUNC )
@@ -328,11 +329,12 @@ struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 				}
 				else
 				{
+					Elf32_Addr addr;
 #ifdef RT_MODULE_DEBUG
 					rt_kprintf("unresolved relocate symbol: %s\n", strtab + sym->st_name);
 #endif
 					/* need to resolve symbol in kernel symbol table */
-					Elf32_Addr addr = rt_module_symbol_find(strtab + sym->st_name);
+					addr = rt_module_symbol_find(strtab + sym->st_name);
 					if (addr != (Elf32_Addr)RT_NULL)
 						rt_module_arm_relocate(module, rel, addr, module_addr);
 					else rt_kprintf("can't find %s in kernel symbol table\n", strtab + sym->st_name);
@@ -346,6 +348,9 @@ struct rt_module* rt_module_load(void* module_ptr, const rt_uint8_t* name)
 	/* init module object container */
 	rt_module_init_object_container(module);
 
+	/* set module defalut clean type */
+	module->parent.flag |= RT_MODULE_FLAG_AUTO_CLEAN;
+	
 	/* create module main thread */
 	module->module_thread = rt_thread_create((const char*)name,
 		module->module_entry, RT_NULL,
@@ -380,7 +385,7 @@ void rt_module_unload(struct rt_module* module)
 	
 	/* release module memory */
 	rt_free(module->module_space);
-	rt_free((void *)module);
+	rt_object_delete((rt_object *)module);
 }
 
 rt_module_t rt_module_find(char* name)