Firefox doesn't like my CI-based URL

Code:
function index()

    {

        /* 

         * find out of the split[cid] cookie is in the house

         */



        if (get_cookie('split' . $this->uri->segment(3)))

            {

                // user has been here, so save some info and send him to correct URL

                $cookie = explode("|", $_COOKIE['split' . $this->uri->segment(3)]);



                $cid = $cookie[0];

                $numhits = $cookie[1];

                $redirnum = $cookie[2];

                $redir = $cookie[3];

                $numhits++;



                //--------------------------------------------------------------------------------

                // see if autoset is on and adjust things accordingly

                //--------------------------------------------------------------------------------

                //    load page table and look at nexturl to see which redirect to use

                $sql = "SELECT autoset, asurl FROM split_pages WHERE splitid = ? LIMIT 1";

                $query = $this->db->query($sql, array($cid));

                if (! $query->num_rows())

                    $errmsg = "::campaign not found::";    

                $row = $query->row();



                if ($row->autoset > 0 && $row->asurl != "")

                    $redir = $row->asurl;





                //    add record to hits table

                $this->db->set('splitid', $cid);

                $this->db->set('redir', $redir);

                $this->db->set('ipaddr', $this->input->ip_address());

                $this->db->set('referer', $this->agent->referrer());

                $this->db->insert('split_hits');

                

                //--------------------------------------------------------------------------------

                // increment the number of hits for the given URL

                //--------------------------------------------------------------------------------

                $this->incnumhits($cid, $redirnum);

                

                //--------------------------------------------------------------------------------

                // set the cookie with new info

                //--------------------------------------------------------------------------------

                

                setcookie("split".$cid, $cid."|".$numhits."|".$redirnum."|".$redir, time()+60*60*24*365, "/", ".sonictoolkit.com");

                

            }

        else

            {

                // first time user!

                

                //    load page table and look at nexturl to see which redirect to use

                $sql = "SELECT * FROM split_pages WHERE splitid = ? LIMIT 1";

                $query = $this->db->query($sql, array($this->uri->segment(3)));

                if (! $query->num_rows())

                    $errmsg = "::campaign not found::";    

                    

                $row = $query->row();

                

                $cid = $row->splitid;

                $myurlpos = $row->nexturl;



                switch ($row->nexturl) {

                case 1:

                    $redirnum = 1;

                    $redir = $row->url1;

                    break;

                case 2:

                    $redirnum = 2;

                    $redir = $row->url2;

                    break;

                case 3:

                    $redirnum = 3;

                    $redir = $row->url3;

                    break;

                }

                

                //--------------------------------------------------------------------------------

                // see if autoset is on and adjust things accordingly

                //--------------------------------------------------------------------------------

                if ($row->autoset > 0 && $row->asurl != "")

                    $redir = $row->asurl;

                

                $maxnext = 0;

                

                if ($row->url1 != "")

                     $maxnext++;

                if ($row->url2 != "")

                     $maxnext++;

                if ($row->url3 != "");

                     $maxnext++;

                

                //    inc nexturl

                $nexturl = $row->nexturl;

                $nexturl++;

                

                //        if nexturl > num urls for this record, set nexturl to 1

                if ($nexturl > $maxnext)

                    $nexturl = 1;



                //--------------------------------------------------------------------------------

                // update the vallue of the nexturl so whomever comes in next knows where to go

                //--------------------------------------------------------------------------------

                $this->db->set('nexturl', $nexturl);

                $this->db->where('splitid', $cid);

                $this->db->update('split_pages');

                //--------------------------------------------------------------------------------

                // increment the number of hits for the given URL

                //--------------------------------------------------------------------------------

                $this->incnumhits($cid, $redirnum);

                

                

                //    store cookie on user computer

                //        cid|numhits|redirnum|redirurl

                $numhits = 0;    // track how many times this user came back before they bought

                setcookie("split".$cid, $cid."|".$numhits."|".$redirnum."|".$redir, time()+60*60*24*365, "/", ".sonictoolkit.com");

                

                //    add record to hits