diff --git a/proguard.flags b/proguard.flags
index be627dbbf..bbffc8a54 100644
--- a/proguard.flags
+++ b/proguard.flags
@@ -26,6 +26,10 @@
 
 # Keep names that are used only by unit tests
 
+-keep class ** {
+  *** *ForTest(...);
+}
+
 -keepclasseswithmembers class com.android.email.GroupMessagingListener {
   *** removeListener(com.android.email.MessagingListener);
 }
@@ -168,4 +172,3 @@
 -keep class org.apache.james.mime4j.message.Message {
   *;
 }
-
diff --git a/src/com/android/email/mail/Message.java b/src/com/android/email/mail/Message.java
index 8906caf30..b23633786 100644
--- a/src/com/android/email/mail/Message.java
+++ b/src/com/android/email/mail/Message.java
@@ -117,7 +117,11 @@ public abstract class Message implements Part, Body {
         return getFlagSet().toArray(new Flag[] {});
     }
 
-    public void setFlag(Flag flag, boolean set) throws MessagingException {
+    /**
+     * Set/clear a flag directly, without involving overrides of {@link #setFlag} in subclasses.
+     * Only used for testing.
+     */
+    public final void setFlagDirectlyForTest(Flag flag, boolean set) throws MessagingException {
         if (set) {
             getFlagSet().add(flag);
         } else {
@@ -125,6 +129,10 @@ public abstract class Message implements Part, Body {
         }
     }
 
+    public void setFlag(Flag flag, boolean set) throws MessagingException {
+        setFlagDirectlyForTest(flag, set);
+    }
+
     /**
      * This method calls setFlag(Flag, boolean)
      * @param flags
diff --git a/src/com/android/email/mail/store/ImapStore.java b/src/com/android/email/mail/store/ImapStore.java
index 9ec912cfe..b4feb1658 100644
--- a/src/com/android/email/mail/store/ImapStore.java
+++ b/src/com/android/email/mail/store/ImapStore.java
@@ -1265,22 +1265,26 @@ public class ImapStore extends Store {
                 uidList.append(messages[i].getUid());
             }
 
-            StringBuilder flagList = new StringBuilder();
-            for (int i = 0, count = flags.length; i < count; i++) {
-                Flag flag = flags[i];
-                if (flag == Flag.SEEN) {
-                    flagList.append(" \\Seen");
-                } else if (flag == Flag.DELETED) {
-                    flagList.append(" \\Deleted");
-                } else if (flag == Flag.FLAGGED) {
-                    flagList.append(" \\Flagged");
+            String allFlags = "";
+            if (flags.length > 0) {
+                StringBuilder flagList = new StringBuilder();
+                for (int i = 0, count = flags.length; i < count; i++) {
+                    Flag flag = flags[i];
+                    if (flag == Flag.SEEN) {
+                        flagList.append(" \\Seen"); // TODO this can be a field of Flag...
+                    } else if (flag == Flag.DELETED) {
+                        flagList.append(" \\Deleted");
+                    } else if (flag == Flag.FLAGGED) {
+                        flagList.append(" \\Flagged");
+                    }
                 }
+                allFlags = flagList.substring(1);
             }
             try {
                 mConnection.executeSimpleCommand(String.format("UID STORE %s %sFLAGS.SILENT (%s)",
                         uidList,
                         value ? "+" : "-",
-                        flagList.substring(1)));        // Remove the first space
+                        allFlags));
             }
             catch (IOException ioe) {
                 throw ioExceptionHandler(mConnection, ioe);
@@ -1513,6 +1517,7 @@ public class ImapStore extends Store {
             this.mSize = size;
         }
 
+        @Override
         public void parse(InputStream in) throws IOException, MessagingException {
             super.parse(in);
         }
diff --git a/tests/src/com/android/email/mail/store/ImapStoreUnitTests.java b/tests/src/com/android/email/mail/store/ImapStoreUnitTests.java
index 3223099b8..661fe5c1b 100644
--- a/tests/src/com/android/email/mail/store/ImapStoreUnitTests.java
+++ b/tests/src/com/android/email/mail/store/ImapStoreUnitTests.java
@@ -16,6 +16,7 @@
 
 package com.android.email.mail.store;
 
+import com.android.email.mail.Address;
 import com.android.email.mail.FetchProfile;
 import com.android.email.mail.Flag;
 import com.android.email.mail.Folder;
@@ -25,8 +26,11 @@ import com.android.email.mail.Part;
 import com.android.email.mail.Transport;
 import com.android.email.mail.Folder.FolderType;
 import com.android.email.mail.Folder.OpenMode;
+import com.android.email.mail.Message.RecipientType;
 import com.android.email.mail.internet.BinaryTempFileBody;
 import com.android.email.mail.internet.MimeUtility;
+import com.android.email.mail.internet.TextBody;
+import com.android.email.mail.store.ImapStore.ImapMessage;
 import com.android.email.mail.transport.DiscourseLogger;
 import com.android.email.mail.transport.MockTransport;
 
@@ -48,6 +52,7 @@ import java.util.Locale;
  */
 @SmallTest
 public class ImapStoreUnitTests extends AndroidTestCase {
+    private final static String[] NO_REPLY = new String[0];
     
     /* These values are provided by setUp() */
     private ImapStore mStore = null;
@@ -555,4 +560,43 @@ public class ImapStoreUnitTests extends AndroidTestCase {
         // And the message is "SEEN".
         assertTrue(message1.isSet(Flag.SEEN));
     }
+
+    public void testAppendMessages() throws Exception {
+        MockTransport mock = openAndInjectMockTransport();
+        setupOpenFolder(mock);
+        mFolder.open(OpenMode.READ_WRITE, null);
+
+        ImapMessage message = (ImapMessage) mFolder.createMessage("1");
+        message.setFrom(new Address("me@test.com"));
+        message.setRecipient(RecipientType.TO, new Address("you@test.com"));
+        message.setMessageId("<message.id@test.com>");
+        message.setFlagDirectlyForTest(Flag.SEEN, true);
+        message.setBody(new TextBody("Test Body"));
+
+        // + go ahead
+        // * 12345 EXISTS
+        // OK [APPENDUID 627684530 17] (Success)
+
+        mock.expect(getNextTag(false) + " APPEND \\\"INBOX\\\" \\(\\\\Seen\\) \\{166\\}",
+                new String[] {"+ go ahead"});
+
+        mock.expectLiterally("From: me@test.com", NO_REPLY);
+        mock.expectLiterally("To: you@test.com", NO_REPLY);
+        mock.expectLiterally("Message-ID: <message.id@test.com>", NO_REPLY);
+        mock.expectLiterally("Content-Type: text/plain;", NO_REPLY);
+        mock.expectLiterally(" charset=utf-8", NO_REPLY);
+        mock.expectLiterally("Content-Transfer-Encoding: base64", NO_REPLY);
+        mock.expectLiterally("", NO_REPLY);
+        mock.expectLiterally("VGVzdCBCb2R5", NO_REPLY);
+        mock.expectLiterally("", new String[] {
+                "* 7 EXISTS",
+                getNextTag(true) + " OK [APPENDUID 1234567 13] (Success)"
+                });
+
+        mFolder.appendMessages(new Message[] {message});
+        mock.close();
+
+        assertEquals("13", message.getUid());
+        assertEquals(7, mFolder.getMessageCount());
+    }
 }
diff --git a/tests/src/com/android/email/mail/transport/MockTransport.java b/tests/src/com/android/email/mail/transport/MockTransport.java
index 3e72cee0a..b1cc3b462 100644
--- a/tests/src/com/android/email/mail/transport/MockTransport.java
+++ b/tests/src/com/android/email/mail/transport/MockTransport.java
@@ -26,6 +26,9 @@ import java.io.OutputStream;
 import java.net.URI;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.regex.Pattern;
+
+import junit.framework.Assert;
 
 /**
  * This is a mock Transport that is used to test protocols that use MailTransport.
@@ -115,7 +118,15 @@ public class MockTransport implements Transport {
         Transaction pair = new Transaction(pattern, responses);
         mPairs.add(pair);
     }
-    
+
+    /**
+     * Same as {@link #expect(String, String[])}, but the first arg is taken literally, rather than
+     * as a regexp.
+     */
+    public void expectLiterally(String literal, String[] responses) {
+        expect("^" + Pattern.quote(literal) + "$", responses);
+    }
+
     /** 
      * Tell the Mock Transport that we expect it to be closed.  This will preserve
      * the remaining entries in the expect() stream and allow us to "ride over" the close (which
@@ -192,7 +203,7 @@ public class MockTransport implements Transport {
     }
 
     public OutputStream getOutputStream() {
-        SmtpSenderUnitTests.assertTrue(mOpen);
+        Assert.assertTrue(mOpen);
         return new MockOutputStream();
     }
 
@@ -302,9 +313,11 @@ public class MockTransport implements Transport {
             Log.d(LOG_TAG, ">>> " + s);
         }
         SmtpSenderUnitTests.assertTrue(mOpen);
-        SmtpSenderUnitTests.assertTrue("Overflow writing to MockTransport", 0 != mPairs.size());
+        SmtpSenderUnitTests.assertTrue("Overflow writing to MockTransport: Getting " + s,
+                0 != mPairs.size());
         Transaction pair = mPairs.remove(0);
-        SmtpSenderUnitTests.assertTrue("Unexpected string written to MockTransport", 
+        SmtpSenderUnitTests.assertTrue("Unexpected string written to MockTransport: Actual=" + s
+                + "  Expected=" + pair.mPattern,
                 pair.mPattern != null && s.matches(pair.mPattern));
         if (pair.mResponses != null) {
             sendResponse(pair.mResponses);