Simple image gallery - strange problem

I'm using the code below to return images in my images directory...you can see the live version at:
http://www.tacticalshooting.com/images/index.php

The problem is that if you click any page other than the first one, it just reloads the first page...I'm missing something that allows the other pages to be viewed - do you see what it might be?

Code:
<?php
if(!isset($rows) || is_nan($rows)){
 $rows=3;
}else if(!is_int($rows)){
 $rows=round($rows);
}
if($rows<1){$rows=1;}
if(!isset($cols) || is_nan($cols)){
 $cols=4;
}else if(!is_int($cols)){
 $cols=round($cols);
}
if($cols<1){$cols=1;}

if(!isset($path)){
  $thisdir=true;
  $path='.';
}
if(!isset($page)){$page=1;}
$dh=opendir($path);
while ($file = readdir($dh)) {
   if (preg_match('/\.(jpg|gif|png)$/i', $file)){
     $files[] = $file;
   }
}

$i = ($page-1)*$rows;
$pages = ceil(count($files) / ($rows*$cols));
echo "<table border=\"1\">\n";
echo " <tr>\n";
echo "  <td colspan=\"$cols\" class=\"nav\">";
if($page>1){
  echo "<a href=\"?page=" . ($page-1);
  if($thisdir!=true){echo "&path=$path";}
  echo "\">[Previous]</a>\n ";
}
echo " Page " . $page . "\n";
if($page<$pages){
  echo "<a href=\"?page=" . ($page+1);
  if($thisdir!=true){echo "&path=$path";}
  echo "\">[Next]</a>\n ";
}
echo "  </td>\n";
echo " </tr>\n";
for(;$i<($page-1)*$rows+$rows;$i++){
  if($i*$cols>count($files)){break;}
  echo " <tr>\n";
  for($j=0;$j<$cols;$j++){
    if($i*$cols+$j >= count($files)){break;}
    $size=getimagesize($path . "/" . $files[$i*$cols+$j]);
    echo "  <td>\n";
    if($size[0]>450){
      $size[0]=(int)($size[0]/4);
      $size[1]=(int)($size[1]/4);
    }else if($size[0]>250){
      $size[0]=(int)($size[0]/2.4);
      $size[1]=(int)($size[1]/2.4);
    }
    echo "   <a href=\"" . $path . "/" . $files[$i*$cols+$j] . "\" target=\"new\">\n";
    echo "    <img border=\"0\" src=\"" . $path . "/" . $files[$i*$cols+$j] . "\" width=\"" . $size[0] . "\" height=\"" . $size[1] . "\" /><br />" . $files[$i*$cols+$j] . "\n   </a>\n";
    echo "  </td>\n";
  }
  echo " </tr>\n";
}
echo " <tr>\n";
echo "   <td colspan=\"$cols\" class=\"nav\">";
for($i=0;$i<$pages;$i++){
 echo "&nbsp;";
 if($i+1!=$page){
  echo "<a href=\"?page=". ($i+1);
  if($thisdir!=true){echo "&path=$path";}
  echo "\">";
 }
 echo "[" . ($i+1) . "]";
 if($i+1!=$page){echo "</a>";}
 echo "&nbsp;";
}
echo "  </td>\n";
echo " </tr>\n";
echo "</table>\n";
?>Start Free Trial