prova con questo...

codice:
    print"  <table cellspacing=\"1\" cellpadding=\"0\" bgcolor=\"#f0f0f0\" width=\"50%\">\n";
    print"    <tr bgcolor=\"#ffffff\"><td colspan=2>Nome</td>\n";
    print"       <td>Dimensione</td>\n";
    print"       <td>Modificato</td>\n";
    print"       <td>Descrizione</td>\n";
    print"       <td></td></tr>\n";

	$workingdir = opendir ($folder);
	$i=0;
	while ($files = readdir($workingdir)) {
	  	  if(eregi(".+\.jpe?g$", $files )||eregi(".+\.gif$", $files )) { 
	    $i++;
	    print"       <tr bgcolor=\"#ffffff\"><td><a href=\"#a\" onclick=\"apri('$folder/$files')\">\n";
	    print"       <img src=\"img/eye.gif\" align=\"middle\" width=\"18\" height=\"18\" border=\"0\" alt=\"esegui\"></a></td>\n";
	    print"          <td>".$files."</td>\n";
	    print"          <td>".filesize($folder."/".$files)." Byte</td>\n";
	    print"          <td>".date("d/m/Y",filemtime($folder."/".$files))."</td>\n";
	    print"          <td>".filetype($folder."/".$files)."</td>\n";
	    print"          <td>[<a href=\"admin.php?tipo=file&act=del&file=$files\">canc</a>]</td></tr>\n";  
          }
	}
	print"       </table>\n";
Ciao,
Banda Bassotti