diff --git a/ext/standard/tests/strings/bug20169.phpt b/ext/standard/tests/strings/bug20169.phpt
new file mode 100644
index 00000000000..0f6890127dd
--- /dev/null
+++ b/ext/standard/tests/strings/bug20169.phpt
@@ -0,0 +1,16 @@
+--FILE--
+<?php
+--TEST--
+Bug #20169
+--FILE--
+<?php
+	set_time_limit(5);
+	$delimiter = "|";
+
+	echo "delimiter: $delimiter\n";
+	implode($delimiter, array("foo", "bar"));
+	echo "delimiter: $delimiter\n";
+?>
+--EXPECT--
+delimiter: |
+delimiter: |