Post new thread phpbb3

I want to adjust this class that is written for phpBB2 into phpBB3 forums.

Here is curl_phpbb.class.php complete code:

http://www.phpkode.com/projects/item/curl-phpbb-functions/

I am working at this function: function new_topic($forum_id, $message, $topic_title)

As I can see, GET and POST params are different for phpBB3 and that is my main problem: to send all form params to server as POST and GET.

Here is html form and submit code:

html form:

<form action="./posting.php?mode=post&amp;f=2&amp;sid=82570fbc6c23aaefb641c86970cfd8a1" method="post" name="postform" enctype="multipart/form-data">

submit button:

<input class="btnmain" type="submit" accesskey="s" tabindex="6" name="post" value="Submit" />

hidden fields:

<td class="cat" colspan="2" align="center"><input type="hidden" name="lastclick" value="1318882908" />
<input type="hidden" name="creation_time" value="1318882908" /> 
<input type="hidden" name="form_token" value="dab9ab1feac70af2eb0a52ce2c86d8bd1c63849b"/>

And here is php code that should send data and match the htmlform:

function new_topic($forum_id, $message, $topic_title)
   {
      global $_SERVER;
   $session_id = "40893d611693d3b32a465d19aa71daa6";
      // Generate post string
      $post_fields = $this->array_to_http(array(
         'post'            => 'Submit',
         'mode'            => 'postform',
         'message'         => $message,
         'f'               => $forum_id,
         'subject'         => $topic_title,
         'disable_bbcode'   => 0,
         'disable_smilies'   => 0,
         'attach_sig'      => 1,
         'topictype'         => 0,
		 'lastclick'    => '1318882908',
		 'creation_time' => '1318882908',
		 'form_token'   =>   'dab9ab1feac70af2eb0a52ce2c86d8bd1c63849b',
      ));
      // Location
      $url_vars = $this->array_to_http(array(
         'mode'   => 'post',
         'f'      => $forum_id,
		 'sid'    => $session_id,
      ));
      // Init curl
      $this->curl = curl_init();
      // Set options
      curl_setopt ( $this->curl, CURLOPT_URL, $this->phpbb_url . 'posting.php?' . $url_vars );
      curl_setopt ( $this->curl, CURLOPT_FOLLOWLOCATION, 0); 
      curl_setopt ( $this->curl, CURLOPT_POST, true );
      curl_setopt ( $this->curl, CURLOPT_POSTFIELDS, $post_fields );
      curl_setopt ( $this->curl, CURLOPT_RETURNTRANSFER, true );
      curl_setopt ( $this->curl, CURLOPT_HEADER, false );
      curl_setopt ( $this->curl, CURLOPT_COOKIE, $this->cookie_name );
      curl_setopt ( $this->curl, CURLOPT_COOKIEJAR, $this->cookie_name );
      curl_setopt ( $this->curl, CURLOPT_COOKIEFILE, $this->cookie_name );
      curl_setopt ( $this->curl, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT'] );
      // Execute request
      $result = curl_exec ( $this->curl );

Here is complete post new topic html code:

http://codepad.org/VtbU7X7A

And here is complete php class code:

http://www.phpkode.com/projects/item/curl-phpbb-functions/

Help me match POST and GET data to send according the html form, so submitting new topic can be successful.