diff --git a/src/tools/docbook/headersampler/HeaderSampler.pl b/src/tools/docbook/headersampler/HeaderSampler.pl
index e87fae97f4..c0c530bc67 100644
--- a/src/tools/docbook/headersampler/HeaderSampler.pl
+++ b/src/tools/docbook/headersampler/HeaderSampler.pl
@@ -78,7 +78,7 @@ sub HandleTextline {
 	SWITCH: {
 
 		# skip 'typedef' or 'struct' region.
-		(/^typedef/ || /^struct/) && do {
+		(/^typedef/ || /^struct/ || /^namespace/) && do {
 			$gIsIgnoring = 1;
 			last SWITCH;
 			};
@@ -105,6 +105,14 @@ sub HandleTextline {
 			last SWITCH;
 			};
 
+		# skip this line if it ends with "}???". for namespace
+		/\}$/ && do {
+			$gSentence = "";
+			@gComment = ();
+			$gIsIgnoring = 0;
+			last SWITCH;
+			};
+
 		# test if end of 'typedef' or 'struct' region.
 			($gIsIgnoring) && do {
 			last SWITCH;