Index: branches/5.0.x/core/admin_templates/custom_fields/custom_fields_list.tpl
===================================================================
diff -u -r12117 -r12382
--- branches/5.0.x/core/admin_templates/custom_fields/custom_fields_list.tpl	(.../custom_fields_list.tpl)	(revision 12117)
+++ branches/5.0.x/core/admin_templates/custom_fields/custom_fields_list.tpl	(.../custom_fields_list.tpl)	(revision 12382)
@@ -68,7 +68,23 @@
 	<inp2:Field field="$field" grid="$grid" no_special="no_special" as_label="1" />
 </inp2:m_DefineElement>
 
-<inp2:m_RenderElement name="grid" PrefixSpecial="cf" IdField="CustomFieldId" grid="Default"/>
+<style type="text/css">
+	tr.row-disabled td {
+		background-color: #FFDFE0;
+	}
+
+	tr.grid-data-row-even.row-disabled td {
+		background-color: #F4D4D5;
+	}
+</style>
+
+<inp2:m_DefineElement name="row_class">
+	<inp2:m_if check="Field" field="IsSystem" db="db">
+		row-disabled
+	</inp2:m_if>
+</inp2:m_DefineElement>
+
+<inp2:m_RenderElement name="grid" PrefixSpecial="cf" IdField="CustomFieldId" grid="Default" row_class_render_as="row_class"/>
 <script type="text/javascript">
 	Grids['cf'].SetDependantToolbarButtons( new Array('edit','delete', 'clone', 'move_down', 'move_up') );
 </script>