not sure if it's good to post the code here, anyway, i get it a try: BACKUP BEFORE U TRY IT
1. put this <?php wp_link_pages(); ?> into single.php
2. open post-template.php. at line 133 , where u see the line : global $post;
add this below it:
$idd = get_the_ID();
$findtitle = mysql_query("SELECT post_title FROM wp_posts WHERE ID = $idd");
$row = mysql_num_rows($findtitle);
$i = 0;
while($row > $i){
$dbrow = mysql_fetch_assoc($findtitle);
$oai = $dbrow['post_title'];
$i++;
}
4. few lines down, you will see this line:
$defaults = array bla bla, and change the Pages: word or delete it if u like.
5. find these lines:
if ( ($i != $page) || ((!$more) && ($page==1)) )
$output .= '</a>';
just above of it, there is a line like this:
$output .= $j;
change it to
$output .= $oai . $j;
that's all. a bit coding/copying but it does work.
if not, i will send the file and u can take a look at it. cheers