diff --git a/cx_Oracle.c b/cx_Oracle.c
index 12950c6..9c497ab 100644
--- a/cx_Oracle.c
+++ b/cx_Oracle.c
@@ -196,12 +196,12 @@ static PyObject* MakeDSN(
         return NULL;
     if (sidObj) {
         connectDataObj = sidObj;
-        format = cxString_FromAscii("(DESCRIPTION=(ADDRESS_LIST=(ADDRESS="
-                "(PROTOCOL=TCP)(HOST=%s)(PORT=%s)))(CONNECT_DATA=(SID=%s)))");
+        format = cxString_FromAscii("(DESCRIPTION=(ADDRESS="
+                "(PROTOCOL=TCP)(HOST=%s)(PORT=%s))(CONNECT_DATA=(SID=%s)))");
     } else {
         connectDataObj = serviceNameObj;
-        format = cxString_FromAscii("(DESCRIPTION=(ADDRESS_LIST=(ADDRESS="
-                "(PROTOCOL=TCP)(HOST=%s)(PORT=%s)))(CONNECT_DATA="
+        format = cxString_FromAscii("(DESCRIPTION=(ADDRESS="
+                "(PROTOCOL=TCP)(HOST=%s)(PORT=%s))(CONNECT_DATA="
                 "(SERVICE_NAME=%s)))");
     }
     if (!format)
diff --git a/test/Connection.py b/test/Connection.py
index eb1ebab..73a1961 100644
--- a/test/Connection.py
+++ b/test/Connection.py
@@ -53,8 +53,8 @@ class TestConnection(TestCase):
 
     def testMakeDSN(self):
         "test making a data source name from host, port and sid"
-        formatString = "(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)" + \
-                "(HOST=%s)(PORT=%d)))(CONNECT_DATA=(SID=%s)))"
+        formatString = "(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)" + \
+                "(HOST=%s)(PORT=%d))(CONNECT_DATA=(SID=%s)))"
         args = ("hostname", 1521, "TEST")
         result = cx_Oracle.makedsn(*args)
         self.assertEqual(result, formatString % args)