Just read the file in and preg_match to get your data....
<?
$fd = fopen($filename);
$source = fread($fd,filesize($filename));
fclose($fd);
preg_match_all('/<myspecaltag>+(.*[<]+)<\/myspecialtag>+/is',$source,$data);
//$data[1] contains all the text between each open and close tag...
print_r($data[1]);
?>