diff --git a/js/src/tests/ecma_5/RegExp/empty-lookahead.js b/js/src/tests/ecma_5/RegExp/empty-lookahead.js
new file mode 100644
index 000000000000..6e2f709e86e4
--- /dev/null
+++ b/js/src/tests/ecma_5/RegExp/empty-lookahead.js
@@ -0,0 +1,8 @@
+//bug 473941
+var regexp;
+
+regexp = /(?=)/;
+assertEq(regexp.test('test'), true);
+
+if (typeof reportCompare === "function")
+  reportCompare(true, true);
diff --git a/js/src/tests/ecma_5/RegExp/jstests.list b/js/src/tests/ecma_5/RegExp/jstests.list
index 0ae8b2ce93f1..500fe55a81e6 100644
--- a/js/src/tests/ecma_5/RegExp/jstests.list
+++ b/js/src/tests/ecma_5/RegExp/jstests.list
@@ -2,3 +2,4 @@ url-prefix ../../jsreftest.html?test=ecma_5/RegExp/
 script 7.8.5-01.js
 script 15.10.5-01.js
 script 15.10.7.5-01.js
+script empty-lookahead.js