Upload Image problem - PHP

some files seem to be uploading and displaying as a string of text in the browser like this … http://thoughtography.net.au/liveinlandscapes/images/folio/abstract01.jpg

other files work fine.

here is the code I am using (free upload script)

<?php?>
<html>
<head>
<title>Live In Landscapes - Image Uploader</title>
<meta name="author" content="Marcus Kazmierczak, marcus@mkaz.com">
<meta name="copyright" content="(c) 2000 mkaz.com">
<meta name="license" content="http://blazonry.com/mklicense.php">
<meta name="origin" content="May 2000">
<?php

if ($REQUEST_METHOD == "POST")
{

    /* SUBMITTED INFORMATION - use what you need
     * temporary filename (pointer): $imgfile
     * original filename           : $imgfile_name
     * size of uploaded file       : $imgfile_size
     * mime-type of uploaded file  : $imgfile_type
     */

     /*== upload directory where the file will be stored
          relative to where script is run ==*/
    
    $uploaddir = "images/folio";
    

    /*== get file extension (fn at bottom of script) ==*/
    /*== checks to see if image file, if not do not allow upload ==*/
    $pext = getFileExtension($imgfile_name);
    $pext = strtolower($pext);
    if (($pext != "jpg")  && ($pext != "jpeg"))
    {
        print "<h1>ERROR</h1>Image Extension Unknown.<br>";
        print "<p>Please upload only a JPEG image with the extension .jpg or .jpeg ONLY<br><br>";
        print "The file you uploaded had the following extension: $pext</p>
";

        /*== delete uploaded file ==*/
        unlink($imgfile);
        exit();
    }


    //-- RE-SIZING UPLOADED IMAGE

    /*== only resize if the image is larger than 250 x 200 ==*/
    $imgsize = GetImageSize($imgfile);

    /*== check size  0=width, 1=height ==*/
    if (($imgsize[0] > 420) || ($imgsize[1] > 315))
    {
        /*== temp image file -- use "tempnam()" to generate the temp
             file name. This is done so if multiple people access the
            script at once they won't ruin each other's temp file ==*/
        $tmpimg = tempnam("/tmp", "MKUP");

        /*== RESIZE PROCESS
             1. decompress jpeg image to pnm file (a raw image type)
             2. scale pnm image
             3. compress pnm file to jpeg image
        ==*/
        
        /*== Step 1: djpeg decompresses jpeg to pnm ==*/
        system("djpeg $imgfile >$tmpimg");
        

        /*== Steps 2&3: scale image using pnmscale and then pipe into cjpeg to output jpeg file ==*/
        system("pnmscale -xy 420 315 $tmpimg | cjpeg -smoo 0 -qual 65 >$imgfile");

        /*== remove temp image ==*/
        unlink($tmpimg);

    }

    /*== setup final file location and name ==*/
    /*== change spaces to underscores in filename  ==*/
    $final_filename = str_replace(" ", "_", $imgfile_name);
    $newfile = $uploaddir . "/$final_filename";
    
    /*== do extra security check to prevent malicious abuse==*/
    if (is_uploaded_file($imgfile))
    {

       /*== move file to proper directory ==*/
       if (!copy($imgfile,"$newfile"))
       {
          /*== if an error occurs the file could not be written, read or possibly does not exist ==*/
          print "Error Uploading File.";
          exit();
       }
     }

    /*== delete the temporary uploaded file ==*/
    unlink($imgfile);

    
    print("<img src=\"$newfile\">");

    /*== DO WHATEVER ELSE YOU WANT
         SUCH AS INSERT DATA INTO A DATABASE  ==*/

}
?>
</head>
<body bgcolor="#FFFFFF">
<h2>Upload and Resize an Image</H2>
<form action="<?=$SCRIPT_NAME; ?>" method="POST" enctype="multipart/form-data">
  <input type="hidden" name="MAX_FILE_SIZE" value="5000000">
  <p>Upload Image:
    <input type="file" name="imgfile">
    <br>
    <font size="1">Click browse to upload a local file</font><br>
    <br>
    <input type="submit" value="Upload Image">
</form>
</body>
</html>
<?php
    /*== FUNCTIONS ==*/

    function getFileExtension($str) {

        $i = strrpos($str,".");
        if (!$i) { return ""; }

        $l = strlen($str) - $i;
        $ext = substr($str,$i+1,$l);

        return $ext;

    }
?>

any ideas?