Add mimetools testcase.
diff --git a/Lib/test/test_mimetools.py b/Lib/test/test_mimetools.py
new file mode 100644
index 0000000..4ee11a1
--- /dev/null
+++ b/Lib/test/test_mimetools.py
@@ -0,0 +1,18 @@
+from test_support import TestFailed
+import mimetools
+
+import string,StringIO
+start = string.letters + "=" + string.digits + "\n"
+for enc in ['7bit','8bit','base64','quoted-printable']:
+    print enc,
+    i = StringIO.StringIO(start)
+    o = StringIO.StringIO()
+    mimetools.encode(i,o,enc)
+    i = StringIO.StringIO(o.getvalue())
+    o = StringIO.StringIO()
+    mimetools.decode(i,o,enc)
+    if o.getvalue()==start:
+        print "PASS"
+    else:
+        print "FAIL"
+        print o.getvalue()