diff -r b72c6db6890b -r 5dc02b23752f tests/auto/qstringlist/tst_qstringlist.cpp
--- a/tests/auto/qstringlist/tst_qstringlist.cpp	Wed Jun 23 19:07:03 2010 +0300
+++ b/tests/auto/qstringlist/tst_qstringlist.cpp	Tue Jul 06 15:10:48 2010 +0300
@@ -77,6 +77,7 @@
     void streamingOperator();
     void join() const;
     void join_data() const;
+    void joinEmptiness() const;
 };
 
 extern const char email[];
@@ -311,5 +312,14 @@
                 << QString("a b c");
 }
 
+void tst_QStringList::joinEmptiness() const
+{
+    QStringList list;
+    QString string = list.join(QString());
+
+    QVERIFY(string.isEmpty());
+    QVERIFY(string.isNull());
+}
+
 QTEST_APPLESS_MAIN(tst_QStringList)
 #include "tst_qstringlist.moc"