Java Applet in Mac FireFox sets multiple DIFFERENT cookies

I've been fighting with this one for a couple days. I'm getting two
(different) cookie headers being set.

Quick Background:
 - Using a TurboGears web application.
 - Embedding an Applet to assist in file uploads (JUpload).
 - Applet uploads the files and sends the data to a secure URL.
 - A session ID preserves the user's login information so they don't
get a 403 or have to login again.
 - Works totally fine in everything EXCEPT FireFox on a Mac (Safari
works fine, as well as FireFox in Windows)

Using Ethereal to look at the HTTP header, there are two "Cookies"
values being set. The one that I set, and some other random one which
I have NO idea where it is coming from. As follows:

POST /import/upload HTTP/1.1
Cookies: tg-visit=2k842fgj237dfkvh232c32hdh3832
Content-length: 123541
<blah blah blah other headers>
Cookies: tg-visit=743jk82hfg94520fng62j8233jfg826

The first tg-visit value (the session id) is correct. The second one
which is the last header being set, is some other id being set. In
Safari the tg-visit value is the same on both lines and it works fine.
Other browsers properly only sets a single line. Firefox on a Mac
gives me two different values, and I have NO idea why.

Code to follow:

<APPLET CODE="foo.bar.myApplet" ARCHIVE="/static/myApplet.jar"
WIDTH="450" HEIGHT="320">');
    <PARAM name="type" value="application/x-java-applet;version=1.4" /
    
<PARAM name="scriptable" value="true" />
    <PARAM name="postURL" value="${postUrl}" />
    <PARAM name="redirectURL" value="${redirectUrl}" />
    <PARAM name="tgVisitValue" value="tg-visit=${tgVisitValue}" />
</APPLET>

I have also tried to use the MAYSCRIPT attribute, but that doesn't
really help.
Using TurboGears which fills in the ${tgVisitValue} properly (which
works fine).

myApplet.java

    this.mycookies = this.getParameter("tgVisitValue",
DEFAULT_COOKIE_STRING);
    if (this.mycookies == DEFAULT_COOKIE_STRING) {
        try
             {
             JSObject window = JSObject.getWindow(this );
             JSObject document =
(JSObject)window.getMember( "document" );

             String cookies =
(String)window.eval("self.document.cookie");
             if (cookies.equals("undefined")) // we're IE
               cookies = (String)document.getMember("cookie");

             // NAOMI
             // get all the unexpired cookies
             // this.mycookies = (String) document.getMember( "cookie" );

             }
        catch ( Exception e )
             {
             this.mycookies = "nocookie=0";
             }
    }

This grabs the cookie value properly, so I don't think there are any
problems there. The code that does all the HTTP magic is here:

try{
      String boundary = "-----------------------------" +
getRandomString();

      url = new URL(uploadURL);
      // Setting up the connection for upload.
      urlConn = url.openConnection();
      urlConn.setRequestProperty("Cookie", this.mycookies);
      urlConn.setDoInput (true);
      urlConn.setDoOutput (true);
      urlConn.setUseCaches (false);
      urlConn.setRequestProperty("Content-length", ""+totalFilesLength);
      urlConn.setRequestProperty("Content-Type",
                                 "multipart/form-data; boundary=" +
                                 boundary.substring(2,
boundary.length()));

      String CRLF = "\r\n";

      urlConn.connect();

      // Retrieve OutputStream For upload (Post).
      dOut = new DataOutputStream(urlConn.getOutputStream());

      // Actual Uploading part.
      StringBuffer sb;
      File f;
      uploadedLength = 0;
      for(int i=0; i < aTotalFiles.length && !stop; i++){
        f = aTotalFiles[i];
        sb = new StringBuffer();
        // Line 1.
        sb.append(boundary);sb.append(CRLF);
        // Line 2.
        sb.append("Content-Disposition: form-data; name=
\"File");sb.append(i);
        sb.append("\"; filename=\"");sb.append(f.toString());
        sb.append("\"");sb.append(CRLF);
        // Line 3 & Empty Line 4.
        sb.append("Content-Type: application/octet-stream");
        sb.append("Content-Length: " + f.length());
        sb.append(CRLF);sb.append(CRLF);

        dOut.writeBytes(sb.toString());
        uploadFileStream(f,dOut);
        dOut.writeBytes(CRLF);
      }

      // Telling the Server we have Finished.
      dOut.writeBytes(boundary);
      dOut.writeBytes("--");
      dOut.writeBytes(CRLF);
      dOut.flush ();

      if(!stop) progress.setString("File(s) uploaded. Wait for server
response!");
      bInp = new BufferedReader(new
InputStreamReader(urlConn.getInputStream ()));

Any ideas?