diff --git a/mozilla/intl/uconv/tests/unit/test_bug383018.js b/mozilla/intl/uconv/tests/unit/test_bug383018.js
new file mode 100644
index 00000000000..ad58921ba22
--- /dev/null
+++ b/mozilla/intl/uconv/tests/unit/test_bug383018.js
@@ -0,0 +1,11 @@
+// Make sure that we can resolve the ascii charset alias to us-ascii
+// (bug 383018)
+
+function run_test() {
+  var ccm = Components.classes["@mozilla.org/charset-converter-manager;1"];
+  var ccms = ccm.getService(Components.interfaces.nsICharsetConverterManager);
+
+  var alias = ccms.getCharsetAlias("ascii");
+  // ascii should be an alias for us-ascii
+  do_check_eq(alias, "us-ascii");
+}