src/share/classes/sun/text/resources/vi/FormatData_vi.java

@@ -104,10 +104,21 @@
                     "Th 5", // abb Thursday
                     "Th 6", // abb Friday
                     "Th 7" // abb Saturday
                 }
             },
+            { "DayNarrows",
+                new String[] {
+                    "CN",
+                    "T2",
+                    "T3",
+                    "T4",
+                    "T5",
+                    "T6",
+                    "T7",
+                }
+            },
             { "AmPmMarkers",
                 new String[] {
                     "SA", // am marker
                     "CH" // pm marker
                 }