diff --git a/hgsane/sane_hg_mdw.cpp b/hgsane/sane_hg_mdw.cpp
index 4e45a53..61aa1a4 100644
--- a/hgsane/sane_hg_mdw.cpp
+++ b/hgsane/sane_hg_mdw.cpp
@@ -357,35 +357,42 @@ namespace local_utility
 		//TRY_MATCH(DRIVER_LOG);
 		//TRY_MATCH(DEVICE_LOG);
 	}
-	static std::string un_json_option_name(int id)
+	static std::string un_json_option_name(int id, int *len)
 	{
-#define FIX_ID_TO_NAME(fid)		\
-	if(id == SANE_OPT_ID_##fid)	\
-		return SANE_STD_OPT_NAME_##fid;
+		int tmp = sizeof(int);
+		if (!len)
+			len = &tmp;
 
-		FIX_ID_TO_NAME(HISTORY_COUNT);
-		FIX_ID_TO_NAME(DRIVER_VERSION);
-		FIX_ID_TO_NAME(MANUFACTURER);
-		FIX_ID_TO_NAME(COPYRIGHT);
-		FIX_ID_TO_NAME(CO_URL);
-		FIX_ID_TO_NAME(CO_TEL);
-		FIX_ID_TO_NAME(CO_ADDR);
-		FIX_ID_TO_NAME(CO_GPS);
-		FIX_ID_TO_NAME(VID);
-		FIX_ID_TO_NAME(PID);
-		FIX_ID_TO_NAME(DEV_NAME);
-		FIX_ID_TO_NAME(DEV_FAMILY);
-		FIX_ID_TO_NAME(ROLLER_COUNT);
-		FIX_ID_TO_NAME(HELP);
-		FIX_ID_TO_NAME(LOGIN);
-		FIX_ID_TO_NAME(LOGOUT);
-		FIX_ID_TO_NAME(DRIVER_LOG);
-		FIX_ID_TO_NAME(DEVICE_LOG);
+#define FIX_ID_TO_NAME(fid, l)			\
+	if(id == SANE_OPT_ID_##fid)			\
+	{									\
+		*len = l;						\
+		return SANE_STD_OPT_NAME_##fid;	\
+	}
 
-		FIX_ID_TO_NAME(DEVICE_SERIAL_NO);
-		FIX_ID_TO_NAME(FIRMWARE_VERSION);
-		FIX_ID_TO_NAME(DEVICE_IP_ADDR);
-		FIX_ID_TO_NAME(DEVICE_MAC_ADDR);
+		FIX_ID_TO_NAME(HISTORY_COUNT, sizeof(int));
+		FIX_ID_TO_NAME(DRIVER_VERSION, 255);
+		FIX_ID_TO_NAME(MANUFACTURER, 255);
+		FIX_ID_TO_NAME(COPYRIGHT, 255);
+		FIX_ID_TO_NAME(CO_URL, 255);
+		FIX_ID_TO_NAME(CO_TEL, 255);
+		FIX_ID_TO_NAME(CO_ADDR, 255);
+		FIX_ID_TO_NAME(CO_GPS, 255);
+		FIX_ID_TO_NAME(VID, sizeof(int));
+		FIX_ID_TO_NAME(PID, sizeof(int));
+		FIX_ID_TO_NAME(DEV_NAME, 255);
+		FIX_ID_TO_NAME(DEV_FAMILY, 255);
+		FIX_ID_TO_NAME(ROLLER_COUNT, sizeof(int));
+		FIX_ID_TO_NAME(HELP, sizeof(int));
+		FIX_ID_TO_NAME(LOGIN, 255);
+		FIX_ID_TO_NAME(LOGOUT, 255);
+		FIX_ID_TO_NAME(DRIVER_LOG, 255);
+		FIX_ID_TO_NAME(DEVICE_LOG, 255);
+
+		FIX_ID_TO_NAME(DEVICE_SERIAL_NO, 255);
+		FIX_ID_TO_NAME(FIRMWARE_VERSION, 255);
+		FIX_ID_TO_NAME(DEVICE_IP_ADDR, 255);
+		FIX_ID_TO_NAME(DEVICE_MAC_ADDR, 255);
 
 		return "";
 	}
@@ -1344,13 +1351,15 @@ bool hg_sane_middleware::get_current_value(scanner_handle handle, const void* op
 {
 	if (IS_PTR_NUMBER(option))
 	{
-		int id = (int)(uint64_t)option;
-		std::string	name(local_utility::un_json_option_name(id));
+		int id = (int)(uint64_t)option,
+			l = 0;
+		std::string	name(local_utility::un_json_option_name(id, &l));
 
 		if(!name.empty())
 		{
 			char	buf[256] = { 0 };
 			long	len = sizeof(buf) - 1;
+			memcpy(buf, value, l);
 			if (hg_scanner_get_parameter(handle, name.c_str(), buf, &len) == SCANNER_ERR_OK)
 			{
 				setv(buf, len, value);
@@ -1769,8 +1778,9 @@ SANE_Status hg_sane_middleware::set_option(SANE_Handle h, const void* option, SA
 			{
 				if (IS_PTR_NUMBER(option))
 				{
-					int id = (int)(uint64_t)option;
-					std::string	name(local_utility::un_json_option_name(id));
+					int id = (int)(uint64_t)option,
+						l = 0;
+					std::string	name(local_utility::un_json_option_name(id, &l));
 					if (!name.empty())
 						return local_utility::scanner_err_2_sane_statu(hg_scanner_set_parameter(handle, name.c_str(), value, 0));
 				}