Problem med rename af fil og automatisk thumb ved upload

Jeg bruger følgende script til at rename, uploade og lave en automatisk thumb af et billede:

///////////// SCRIPT START /////////////////////
<?php
include("connection.php");

$updir = $_SERVER["DOCUMENT_ROOT"]."/test/upload";  // Definer stien til dit oploadbibliotek
$aft = array('image/jpeg','image/pjpeg','image/png'); // De filtyper der kan uploades

/*
    Function checkgd()
    checks the version of gd, and returns "yes" when it's higher than 2
*/
function checkgd(){
    $gd2="";
    ob_start();
    phpinfo(8);
    $phpinfo=ob_get_contents();
    ob_end_clean();
    $phpinfo=strip_tags($phpinfo);
    $phpinfo=stristr($phpinfo,"gd version");
    $phpinfo=stristr($phpinfo,"version");
    preg_match('/\d/',$phpinfo,$gd);
    if ($gd[0]=='2'){$gd2="yes";}
    return $gd2;
}

/*
    Function ditchtn($arr,$thumbname)
    filters out thumbnails
*/
function ditchtn($arr,$thumbname){
    foreach ($arr as $item){
        if (!preg_match("/^".$thumbname."/",$item)){$tmparr[]=$item;}
    }
    return $tmparr;
}

/*
    Function createthumb($name,$filename,$new_w,$new_h)
    creates a resized image
    variables:
    $name        Original filename
    $filename    Filename of the resized image
    $new_w        width of resized image
    $new_h        height of resized image
*/   
function createthumb($name,$filename,$new_w,$new_h){
    global $gd2;
    $system=explode(".",$name);
    echo $name." :name<br />";
    echo $system[4]." :system[4]<br />";

    if (preg_match("/jpg|jpeg/",$system[4])){$src_img=imagecreatefromjpeg($name);}
    if (preg_match("/png/",$system[4])){$src_img=imagecreatefrompng($name);}
    $old_x=imageSX($src_img);
    $old_y=imageSY($src_img);
    if ($old_x > $old_y) {
        $thumb_w=$new_w;
        $thumb_h=$old_y*($new_h/$old_x);
    }
    if ($old_x < $old_y) {
        $thumb_w=$old_x*($new_w/$old_y);
        $thumb_h=$new_h;
    }
    if ($old_x == $old_y) {
        $thumb_w=$new_w;
        $thumb_h=$new_h;
    }
    if ($gd2==""){
        $dst_img=ImageCreate($thumb_w,$thumb_h);
        imagecopyresized($dst_img,$src_img,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y);
    }else{
        $dst_img=ImageCreateTrueColor($thumb_w,$thumb_h);
        imagecopyresampled($dst_img,$src_img,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y);
    }
    if (preg_match("/png/",$system[1])){
        imagepng($dst_img,$filename);
    } else {
        imagejpeg($dst_img,$filename);
    }
    imagedestroy($dst_img);
    imagedestroy($src_img);
}

/*
        Function directory($directory,$filters)
        reads the content of $directory, takes the files that apply to $filter
        and returns an array of the filenames.
        You can specify which files to read, for example
        $files = directory(".","jpg,gif");
                gets all jpg and gif files in this directory.
        $files = directory(".","all");
                gets all files.
*/
function directory($dir,$filters){
    $handle=opendir($dir);
    $files=array();
    if ($filters == "all"){while(($file = readdir($handle))!==false){$files[] = $file;}}
    if ($filters != "all"){
        $filters=explode(",",$filters);
        while (($file = readdir($handle))!==false) {
            for ($f=0;$f<sizeof($filters);$f++):
                $system=explode(".",$file);
                if ($system[1] == $filters[$f]){$files[] = $file;}
            endfor;
        }
    }
    closedir($handle);
    return $files;
}

?>
<html>
<head>
<title>Untitled Document</title>
<link href="scroll.css" type="text/css" rel="stylesheet">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body bgcolor="#D0D0D0" text="#000000">
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">upload</font>
<br><br>
<?php

if (isset($_GET['mode']) && $_GET['mode'] == "upload") {
  $galleri = $_POST['ddgalleri'];
  $newfilename = $updir."/".$galleri."_".$_FILES['fil']['name'];
  echo $newfilename." :newfilename<br />";

    if (empty($_REQUEST['fil'])) {
        echo "Du skal vælge en fil";
    }
    else {

      if (in_array($_FILES['fil']['type'],$aft)) {
      if (move_uploaded_file($_FILES['fil']['tmp_name'], $newfilename)) {
        $gd2=checkgd();
        createthumb($newfilename,$updir."/"."thumb_".$newfilename,100,100);

        $imginfo = getimagesize($newfilename);
        $imgwidth = $imginfo[0];  //bredde i pixels
        $imgheight = $imginfo[1]; //højde i pixels
        $imgtype = $imginfo[2];  //jpg, gif, bmp osv
        $imghtml = $imginfo[3];  //height="yyy" width="xxx" - for use directly in html
            Echo "Alt OK<br />";
            Echo $_REQUEST['tekst'];
            }
            else {}
        }
        else {
              echo "Filtypen er ikke korrekt!";
        }   
    }

}

elseif (empty($_GET['mode'])) {
    ?>

    <form action="test3.php?mode=upload" method="post" enctype="multipart/form-data">
    <input type="hidden" name="MAX_FILE_SIZE" value="100000">
    <?php
    $res = mysql_query("SELECT * FROM gallerier");
    echo "<select name=ddgalleri size=1>";
    while($row = mysql_fetch_array($res)) {
    echo "<option value=".$row["galleriid"].">".$row["galleri"]."</option>";
    }
    echo "</select><br />";

    mysql_close();
    ?>
    <input type="file" name="fil"><br />
    <input type="text" name="tekst">
    <br /><br />
    <input type="submit" name="submit" value="Upload" >
    </form>

    <?php

}
else {
    echo "Bad guy!";
}
?>

</body>
</html>
////////////// SCRIPT SLUT /////////////////////

Fejlmeddelelse:
/customers/silkeborgbasketball.dk/silkeborgbasketball.dk/httpd.www/test/upload/1_Vinter.jpg :newfilename
/customers/silkeborgbasketball.dk/silkeborgbasketball.dk/httpd.www/test/upload/1_Vinter.jpg :name
jpg :system[4]

Warning: imagejpeg: unable to open '/customers/silkeborgbasketball.dk/silkeborgbasketball.dk/httpd.www/test/upload/thumb_/customers/silkeborgbasketball.dk/silkeborgbasketball.dk/httpd.www/test/upload/1_Vinter.jpg' for writing in /customers/silkeborgbasketball.dk/silkeborgbasketball.dk/httpd.www/test/test3.php on line 77
Alt OK

What to do?