diff --git a/bin/tests/system/dlzexternal/ns1/named.conf.in b/bin/tests/system/dlzexternal/ns1/named.conf.in
index 58c4892ab3..5809d1ef2c 100644
--- a/bin/tests/system/dlzexternal/ns1/named.conf.in
+++ b/bin/tests/system/dlzexternal/ns1/named.conf.in
@@ -61,7 +61,7 @@ dlz "unsearched2" {
 };
 
 dlz redzone {
-	database "dlopen ../driver.so .";
+	database "dlopen ../driver.@SO@ .";
 	search no;
 };