--- zabbix-2.5.0/frontends/php/include/classes/items/CHelpItems.php.orig	2015-06-21 23:37:45.000000000 +0000
+++ zabbix-2.5.0/frontends/php/include/classes/items/CHelpItems.php	2015-07-19 10:15:02.286312222 +0000
@@ -892,7 +892,7 @@
 				],
 				[
 					'key' => 'zabbix[items_unsupported]',
-					'description' => _('Number of unsupported items in Zabbix database.')
+					'description' => _('Number of unsupported items in Zabbix database. Optionally add ,host to only count the items of this host.')
 				],
 				[
 					'key' => 'zabbix[java,,<param>]',
--- a/src/libs/zbxdbcache/dbconfig.c	2015-02-23 13:28:13.000000000 +0100
+++ b/src/libs/zbxdbcache/dbconfig.c	2015-04-08 12:57:58.818671429 +0200
@@ -6325,7 +6325,7 @@
  * Return value: the number of active unsupported items                       *
  *                                                                            *
  ******************************************************************************/
-int	DCget_item_unsupported_count()
+int	DCget_item_unsupported_count(zbx_uint64_t hostid)
 {
 	int			count = 0;
 	zbx_hashset_iter_t	iter;
@@ -6339,6 +6339,9 @@
 	{
 		const ZBX_DC_HOST	*dc_host;
 
+		if (hostid != 0 && hostid != dc_item->hostid)
+			continue;
+		
 		if (ITEM_STATUS_ACTIVE != dc_item->status || ITEM_STATE_NOTSUPPORTED != dc_item->state)
 			continue;
 
--- zabbix-2.5.0/src/zabbix_server/poller/checks_internal.c.orig	2015-04-24 07:53:31.000000000 +0000
+++ zabbix-2.5.0/src/zabbix_server/poller/checks_internal.c	2015-07-19 10:21:03.494643528 +0000
@@ -97,15 +97,32 @@
 
 		SET_UI64_RESULT(result, DCget_item_count());
 	}
-	else if (0 == strcmp(tmp, "items_unsupported"))		/* zabbix["items_unsupported"] */
+	else if (0 == strcmp(tmp, "items_unsupported"))		/* zabbix[items_unsupported,<host>] */
 	{
-		if (1 != nparams)
+		zbx_uint64_t		hostid = 0;
+
+		if (1 > nparams || 2 < nparams)
 		{
 			error = zbx_strdup(error, "Invalid number of parameters.");
 			goto out;
 		}
 
-		SET_UI64_RESULT(result, DCget_item_unsupported_count());
+		if ( 2 == nparams )
+		{
+			get_param(params, 2, tmp, sizeof(tmp));
+			
+			if (0 != strcmp(tmp, "host"))
+			{
+				error = zbx_strdup(error, "Invalid second parameter.");
+				goto notsupported;
+			}
+			else
+			{
+				hostid = item->host.hostid;
+			}
+		}
+
+		SET_UI64_RESULT(result, DCget_item_unsupported_count(hostid));
 	}
 	else if (0 == strcmp(tmp, "hosts"))			/* zabbix["hosts"] */
 	{