Index: branches/RC/core/units/modules/modules_event_handler.php
===================================================================
diff -u -N -r10832 -r10846
--- branches/RC/core/units/modules/modules_event_handler.php	(.../modules_event_handler.php)	(revision 10832)
+++ branches/RC/core/units/modules/modules_event_handler.php	(.../modules_event_handler.php)	(revision 10846)
@@ -45,21 +45,47 @@
 		function moduleAction(&$event)
 		{
 			if ($this->Application->CheckPermission('SYSTEM_ACCESS.READONLY', 1)) {
-				return;
+				return ;
 			}
 
 			$object =& $event->getObject( Array('skip_autoload' => true) );
 			$ids = $this->StoreSelectedIDs($event);
 
 
-			if (!$ids) return true;
+			if (!$ids) {
+				return true;
+			}
 
 			$status_field = array_shift( $this->Application->getUnitOption($event->Prefix, 'StatusField') );
 
-			foreach($ids as $id)
-			{
+			if ($event->Name == 'OnMassDecline') {
+				$interface_modules = Array ('In-Portal', 'Proj-Base');
+
+				foreach ($interface_modules as $module_index => $interface_module) {
+					if (!$this->Application->findModule('Name', $interface_module)) {
+						// remove already disabled interface modules
+						unset($interface_modules[$module_index]);
+					}
+				}
+			}
+
+			foreach ($ids as $id) {
+				if ($event->Name == 'OnMassDecline') {
+					if (in_array($id, $interface_modules) && count($interface_modules) == 1) {
+						// don't allow to disable both interface modules
+						continue;
+					}
+
+					unset($interface_modules[ array_search($id, $interface_modules) ]);
+				}
+
+				if ($id == 'Core') {
+					// don't allow any kind of manupulations with kernel
+					continue;
+				}
+
 				$object->Load($id);
-				if ($object->GetID() == 'In-Portal') continue;
+
 				$object->SetDBField($status_field, $event->Name == 'OnMassApprove' ? 1 : 0);
 
 				if ($object->Update()) {