diff --git a/Lib/test/output/test_MimeWriter b/Lib/test/output/test_MimeWriter
deleted file mode 100644
index 9b97d93..0000000
--- a/Lib/test/output/test_MimeWriter
+++ /dev/null
@@ -1,110 +0,0 @@
-test_MimeWriter
-From: bwarsaw@cnri.reston.va.us
-Date: Mon Feb 12 17:21:48 EST 1996
-To: kss-submit@cnri.reston.va.us
-MIME-Version: 1.0
-Content-Type: multipart/knowbot;
-    boundary="801spam999";
-    version="0.1"
-
-This is a multi-part message in MIME format.
-
---801spam999
-Content-Type: multipart/knowbot-metadata;
-    boundary="802spam999"
-
-
---802spam999
-Content-Type: message/rfc822
-KP-Metadata-Type: simple
-KP-Access: read-only
-
-KPMD-Interpreter: python
-KPMD-Interpreter-Version: 1.3
-KPMD-Owner-Name: Barry Warsaw
-KPMD-Owner-Rendezvous: bwarsaw@cnri.reston.va.us
-KPMD-Home-KSS: kss.cnri.reston.va.us
-KPMD-Identifier: hdl://cnri.kss/my_first_knowbot
-KPMD-Launch-Date: Mon Feb 12 16:39:03 EST 1996
-
---802spam999
-Content-Type: text/isl
-KP-Metadata-Type: complex
-KP-Metadata-Key: connection
-KP-Access: read-only
-KP-Connection-Description: Barry's Big Bass Business
-KP-Connection-Id: B4
-KP-Connection-Direction: client
-
-INTERFACE Seller-1;
-
-TYPE Seller = OBJECT
-    DOCUMENTATION "A simple Seller interface to test ILU"
-    METHODS
-            price():INTEGER,
-    END;
-
---802spam999
-Content-Type: message/external-body;
-    access-type="URL";
-    URL="hdl://cnri.kss/generic-knowbot"
-
-Content-Type: text/isl
-KP-Metadata-Type: complex
-KP-Metadata-Key: generic-interface
-KP-Access: read-only
-KP-Connection-Description: Generic Interface for All Knowbots
-KP-Connection-Id: generic-kp
-KP-Connection-Direction: client
-
-
---802spam999--
-
---801spam999
-Content-Type: multipart/knowbot-code;
-    boundary="803spam999"
-
-
---803spam999
-Content-Type: text/plain
-KP-Module-Name: BuyerKP
-
-class Buyer:
-    def __setup__(self, maxprice):
-        self._maxprice = maxprice
-
-    def __main__(self, kos):
-        """Entry point upon arrival at a new KOS."""
-        broker = kos.broker()
-        # B4 == Barry's Big Bass Business :-)
-        seller = broker.lookup('Seller_1.Seller', 'B4')
-        if seller:
-            price = seller.price()
-            print 'Seller wants $', price, '... '
-            if price > self._maxprice:
-                print 'too much!'
-            else:
-                print "I'll take it!"
-        else:
-            print 'no seller found here'
-
---803spam999--
-
---801spam999
-Content-Type: multipart/knowbot-state;
-    boundary="804spam999"
-KP-Main-Module: main
-
-
---804spam999
-Content-Type: text/plain
-KP-Module-Name: main
-
-# instantiate a buyer instance and put it in a magic place for the KOS
-# to find.
-__kp__ = Buyer()
-__kp__.__setup__(500)
-
---804spam999--
-
---801spam999--
diff --git a/Lib/test/test_MimeWriter.py b/Lib/test/test_MimeWriter.py
index 5041105..b7d37b2 100644
--- a/Lib/test/test_MimeWriter.py
+++ b/Lib/test/test_MimeWriter.py
@@ -7,6 +7,8 @@
 
 """
 
+import unittest, sys, StringIO
+from test.test_support import run_unittest
 
 from MimeWriter import MimeWriter
 
@@ -77,94 +79,213 @@
         ]
 
 
-def main():
-    import sys
+OUTPUT = '''\
+From: bwarsaw@cnri.reston.va.us
+Date: Mon Feb 12 17:21:48 EST 1996
+To: kss-submit@cnri.reston.va.us
+MIME-Version: 1.0
+Content-Type: multipart/knowbot;
+    boundary="801spam999";
+    version="0.1"
 
-    # Toplevel headers
+This is a multi-part message in MIME format.
 
-    toplevel = MimeWriter(sys.stdout)
-    toplevel.addheader("From", "bwarsaw@cnri.reston.va.us")
-    toplevel.addheader("Date", "Mon Feb 12 17:21:48 EST 1996")
-    toplevel.addheader("To", "kss-submit@cnri.reston.va.us")
-    toplevel.addheader("MIME-Version", "1.0")
-
-    # Toplevel body parts
-
-    f = toplevel.startmultipartbody("knowbot", "801spam999",
-                                    [("version", "0.1")], prefix=0)
-    f.write("This is a multi-part message in MIME format.\n")
-
-    # First toplevel body part: metadata
-
-    md = toplevel.nextpart()
-    md.startmultipartbody("knowbot-metadata", "802spam999")
-
-    # Metadata part 1
-
-    md1 = md.nextpart()
-    md1.addheader("KP-Metadata-Type", "simple")
-    md1.addheader("KP-Access", "read-only")
-    m = MimeWriter(md1.startbody("message/rfc822"))
-    for key, value in SIMPLE_METADATA:
-        m.addheader("KPMD-" + key, value)
-    m.flushheaders()
-    del md1
-
-    # Metadata part 2
-
-    md2 = md.nextpart()
-    for key, value in COMPLEX_METADATA:
-        md2.addheader("KP-" + key, value)
-    f = md2.startbody("text/isl")
-    f.write(SELLER)
-    del md2
-
-    # Metadata part 3
-
-    md3 = md.nextpart()
-    f = md3.startbody("message/external-body",
-                      [("access-type", "URL"),
-                       ("URL", "hdl://cnri.kss/generic-knowbot")])
-    m = MimeWriter(f)
-    for key, value in EXTERNAL_METADATA:
-        md3.addheader("KP-" + key, value)
-    md3.startbody("text/isl")
-    # Phantom body doesn't need to be written
-
-    md.lastpart()
-
-    # Second toplevel body part: code
-
-    code = toplevel.nextpart()
-    code.startmultipartbody("knowbot-code", "803spam999")
-
-    # Code: buyer program source
-
-    buyer = code.nextpart()
-    buyer.addheader("KP-Module-Name", "BuyerKP")
-    f = buyer.startbody("text/plain")
-    f.write(BUYER)
-
-    code.lastpart()
-
-    # Third toplevel body part: state
-
-    state = toplevel.nextpart()
-    state.addheader("KP-Main-Module", "main")
-    state.startmultipartbody("knowbot-state", "804spam999")
-
-    # State: a bunch of assignments
-
-    st = state.nextpart()
-    st.addheader("KP-Module-Name", "main")
-    f = st.startbody("text/plain")
-    f.write(STATE)
-
-    state.lastpart()
-
-    # End toplevel body parts
-
-    toplevel.lastpart()
+--801spam999
+Content-Type: multipart/knowbot-metadata;
+    boundary="802spam999"
 
 
-main()
+--802spam999
+Content-Type: message/rfc822
+KP-Metadata-Type: simple
+KP-Access: read-only
+
+KPMD-Interpreter: python
+KPMD-Interpreter-Version: 1.3
+KPMD-Owner-Name: Barry Warsaw
+KPMD-Owner-Rendezvous: bwarsaw@cnri.reston.va.us
+KPMD-Home-KSS: kss.cnri.reston.va.us
+KPMD-Identifier: hdl://cnri.kss/my_first_knowbot
+KPMD-Launch-Date: Mon Feb 12 16:39:03 EST 1996
+
+--802spam999
+Content-Type: text/isl
+KP-Metadata-Type: complex
+KP-Metadata-Key: connection
+KP-Access: read-only
+KP-Connection-Description: Barry's Big Bass Business
+KP-Connection-Id: B4
+KP-Connection-Direction: client
+
+INTERFACE Seller-1;
+
+TYPE Seller = OBJECT
+    DOCUMENTATION "A simple Seller interface to test ILU"
+    METHODS
+            price():INTEGER,
+    END;
+
+--802spam999
+Content-Type: message/external-body;
+    access-type="URL";
+    URL="hdl://cnri.kss/generic-knowbot"
+
+Content-Type: text/isl
+KP-Metadata-Type: complex
+KP-Metadata-Key: generic-interface
+KP-Access: read-only
+KP-Connection-Description: Generic Interface for All Knowbots
+KP-Connection-Id: generic-kp
+KP-Connection-Direction: client
+
+
+--802spam999--
+
+--801spam999
+Content-Type: multipart/knowbot-code;
+    boundary="803spam999"
+
+
+--803spam999
+Content-Type: text/plain
+KP-Module-Name: BuyerKP
+
+class Buyer:
+    def __setup__(self, maxprice):
+        self._maxprice = maxprice
+
+    def __main__(self, kos):
+        """Entry point upon arrival at a new KOS."""
+        broker = kos.broker()
+        # B4 == Barry's Big Bass Business :-)
+        seller = broker.lookup('Seller_1.Seller', 'B4')
+        if seller:
+            price = seller.price()
+            print 'Seller wants $', price, '... '
+            if price > self._maxprice:
+                print 'too much!'
+            else:
+                print "I'll take it!"
+        else:
+            print 'no seller found here'
+
+--803spam999--
+
+--801spam999
+Content-Type: multipart/knowbot-state;
+    boundary="804spam999"
+KP-Main-Module: main
+
+
+--804spam999
+Content-Type: text/plain
+KP-Module-Name: main
+
+# instantiate a buyer instance and put it in a magic place for the KOS
+# to find.
+__kp__ = Buyer()
+__kp__.__setup__(500)
+
+--804spam999--
+
+--801spam999--
+'''
+
+class MimewriterTest(unittest.TestCase):
+    
+    def test(self):
+        buf = StringIO.StringIO()
+
+        # Toplevel headers
+
+        toplevel = MimeWriter(buf)
+        toplevel.addheader("From", "bwarsaw@cnri.reston.va.us")
+        toplevel.addheader("Date", "Mon Feb 12 17:21:48 EST 1996")
+        toplevel.addheader("To", "kss-submit@cnri.reston.va.us")
+        toplevel.addheader("MIME-Version", "1.0")
+
+        # Toplevel body parts
+
+        f = toplevel.startmultipartbody("knowbot", "801spam999",
+                                        [("version", "0.1")], prefix=0)
+        f.write("This is a multi-part message in MIME format.\n")
+
+        # First toplevel body part: metadata
+
+        md = toplevel.nextpart()
+        md.startmultipartbody("knowbot-metadata", "802spam999")
+
+        # Metadata part 1
+
+        md1 = md.nextpart()
+        md1.addheader("KP-Metadata-Type", "simple")
+        md1.addheader("KP-Access", "read-only")
+        m = MimeWriter(md1.startbody("message/rfc822"))
+        for key, value in SIMPLE_METADATA:
+            m.addheader("KPMD-" + key, value)
+        m.flushheaders()
+        del md1
+
+        # Metadata part 2
+
+        md2 = md.nextpart()
+        for key, value in COMPLEX_METADATA:
+            md2.addheader("KP-" + key, value)
+        f = md2.startbody("text/isl")
+        f.write(SELLER)
+        del md2
+
+        # Metadata part 3
+
+        md3 = md.nextpart()
+        f = md3.startbody("message/external-body",
+                          [("access-type", "URL"),
+                           ("URL", "hdl://cnri.kss/generic-knowbot")])
+        m = MimeWriter(f)
+        for key, value in EXTERNAL_METADATA:
+            md3.addheader("KP-" + key, value)
+        md3.startbody("text/isl")
+        # Phantom body doesn't need to be written
+
+        md.lastpart()
+
+        # Second toplevel body part: code
+
+        code = toplevel.nextpart()
+        code.startmultipartbody("knowbot-code", "803spam999")
+
+        # Code: buyer program source
+
+        buyer = code.nextpart()
+        buyer.addheader("KP-Module-Name", "BuyerKP")
+        f = buyer.startbody("text/plain")
+        f.write(BUYER)
+
+        code.lastpart()
+
+        # Third toplevel body part: state
+
+        state = toplevel.nextpart()
+        state.addheader("KP-Main-Module", "main")
+        state.startmultipartbody("knowbot-state", "804spam999")
+
+        # State: a bunch of assignments
+
+        st = state.nextpart()
+        st.addheader("KP-Module-Name", "main")
+        f = st.startbody("text/plain")
+        f.write(STATE)
+
+        state.lastpart()
+
+        # End toplevel body parts
+
+        toplevel.lastpart()
+
+        self.assertEqual(buf.getvalue(), OUTPUT)
+
+def test_main():
+    run_unittest(MimewriterTest)
+
+if __name__ == '__main__':
+    test_main()