Unable to get javamail POP3Folder to delete any messages

I'm trying to setup some email processing using javamail, but have been completely unable to get it to even delete a message.

	Properties props = System.getProperties();
	props.setProperty("mail.pop3.rsetbeforequit", "0");
	Session session = Session.getInstance(props, null);
	Store store = session.getStore("pop3");
	store.connect(account.getHost(), account.getUserid(), account.getPassword());
	Folder folder = store.getFolder("INBOX");
	folder.open(Folder.READ_ONLY);
	int msgCnt = folder.getMessageCount();

	for (int idx = 1; (idx <= msgCnt); idx++) {
		Message msg = folder.getMessage(idx);
		// Do Stuff here...

		// doesn't work
		msg.setFlag(Flags.Flag.DELETED, true);
		
                // doesn't work
		// Flags flags = new Flags( Flags.Flag.DELETED);
		// folder.setFlags(idx, idx, flags, true);

		// doesn't work
		// Flags flags = new Flags(Flags.Flag.DELETED);
		// Message[] msgs = new Message[1];
		// msgs[0] = msg;
		// folder.setFlags(msgs, flags, true);
	}

	folder.close(true);

It doesn't seem to matter what I do, the message never gets deleted.

What am I doing wrong?