php fatal error

Hi - !

I have beig trying to use that php software name popper, and when ever I try to run that file it just says that fatal error, its saying that class.db_tool.in.php on line 80 , here is the class.db_tool.in.php

Fatal error: Failed opening required '/home/admin/www/../popper.inc.php' (include_path='.:/usr/local/lib/php') in /home/admin/www/popper/class.db_tool.inc.php on line 80
----------------------------------------------------------
<?php

/*========================================================================
A POP3 web mail-client written in PHP
Copyright (C) 2000 by Jean-Pierre Bergamin

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License.

For more information see the file gpl.txt or go to
http://www.gnu.org/copyleft/gpl.html

==========================================================================*/

class db_tool {

      var $db_data_inc = "";                  // contains the vars $host, $user, $pass
      var $db_link;
      // Overridable methods
      //
      // Adapt to other databases
      function db_tool($data_inc) {
            $this->db_data_inc = $data_inc;
      }

      function db_query($query) {
            return mysql_query($query);
      }

      function db_connect($host, $user, $pwd) {
            return @mysql_connect($host, $user, $pwd);
      }

      function fetch_array($res) {
            return mysql_fetch_array($res);
      }

      function fetch_row($res) {
            return mysql_fetch_row($res);
      }

      function insert_id() {
            return mysql_insert_id();
      }

      function affected_rows() {
            return mysql_affected_rows($this->db_link);
      }

      function db_error() {
            return mysql_error();
      }

      function db_data_inc($file) {
            if (empty($file)) {
                  // oops!
                  return;
            }
            $this->db_data_inc = $file;
      }

      function query($query, $link) {
            return mysql_query($query, $link);
      }

      // Private functions
      //
      // Don't use them in your code


      // Get the link to the db
      function link_db() {
            global $strings;
            $doc_root = getenv("DOCUMENT_ROOT");
            $path = $doc_root;
            if ($GLOBALS["in_docroot"] === false) {
                  $path .= "/..";
            }
            $path .= "/".$this->db_data_inc;
            require($path);
            $this->db_link = $this->db_connect($host, $user, $pass)
                  or die ($strings["l_ServerConnect"]."<br>".$this->db_error());

            $query = "USE $dbname";
            $this->query($query, $this->db_link)
                  or die ($strings["l_OpenDB"]."<br>".$this->db_error());
      }

      // Public functions

      // perform the query
      function db_query($query) {
            $this->link_db();
            return $this->query($query, $this->db_link);
      }

      function insert($tablename /* var. no. of strings of the variable names*/) {
            $num_args = func_num_args();
            $args = func_get_args();
            // Skip the table name as argument
            for($i = 1; $i < $num_args; $i++) {
                  $var_name = func_get_arg($i);
                  $col_names .= $var_name." ";
                  $values .= $GLOBALS["$var_name"]." ";
            }

            $col_names = str_replace(" ", ", ", trim($col_names));
            $values = str_replace(" ", ", ", trim($values));
            $query = "INSERT INTO $tablename ($col_names) VALUES ($values)";
            //echo $query;
            return;
            $res = $this->query($query);
            if ($res == 0) {
                  return 0;
            }

            return $this->insert_id();
      }

      function update($tablename, $where /* var. no. of strings of the variable names*/) {
            $num_args = func_num_args();
            $args = func_get_args();
            // Skip the table name and the WHERE clause arguments
            for($i = 2; $i < $num_args; $i++) {
                  $var_name = func_get_arg($i);
                  $update .= $var_name."=".$GLOBALS["$var_name"]." ";
            }
            $update = str_replace(" ", ", ", trim($update));

            $query = "UPDATE $tablename SET $update WHERE $where";
            //echo $query;
            return;
            $res = $this->query($query);
            if ($res == 0) {
                  return 0;
            }

            return $this->insert_id();
      }

      function store($tablename /* var. no. of strings of the variable names*/ /*the last arg is the where clause, pass empty string if it's an insert*/) {
            global $update;

            $num_args = func_num_args();
            $args = func_get_args();

            if (isset($update) && $update == 1) {
                  $num_args = func_num_args();
                  $args = func_get_args();
                  // Skip the table name and the WHERE clause arguments
                  for($i = 1; $i < $num_args - 1; $i++) {
                        $var_name = func_get_arg($i);
                        if (isset($GLOBALS[$var_name])) {
                              $update_str .= $var_name."='".$GLOBALS["$var_name"]."', ";
                        }
                  }

                  //$update_str = str_replace("' '", "', '", trim($update_str));
                  $update_str = ereg_replace(", $", "", $update_str);
                  $where = func_get_arg($num_args - 1);
                  $query = "UPDATE $tablename SET $update_str WHERE $where";
                  /*echo $query;
                  echo("<br>WHERE: $where");*/

                  $res = $this->db_query($query);
                  if ($res == 0) {
                        echo $this->db_error();
                        return 0;
                  }

                  return 1;
            }
            else {
                  // Skip the table name as argument
                  for($i = 1; $i < $num_args; $i++) {
                        $var_name = func_get_arg($i);
                        if (isset($GLOBALS[$var_name])) {
                              $col_names .= $var_name." ";
                              $values .= "'".addslashes($GLOBALS[$var_name])."' ";
                        }
                  }

                  $col_names = str_replace(" ", ", ", trim($col_names));
                  $values = str_replace("' '", "', '", trim($values));
                  $query = "INSERT INTO $tablename ($col_names) VALUES ($values)";

                  $res = $this->db_query($query);
                  if ($res == 0) {
                        //echo $this->db_error();
                        //echo "<br>Errno: ".mysql_errno();
                        return 0;
                  }

                  return $this->insert_id();
            }
      }


}
?>

I also try to make a database, like :-

mysql mail --user=dbusername -p < popper.mysql
Enter password:
ERROR 1045: Access denied for user: 'dbusername@localhost' (Using password: YES)

Why its saying Access Denied, I have a root access, then why is that..