[kh99]

You could do this, using hook newpost_process:

PHP Code:

$post1=array( 
'a','b','c' ,'d' 
); 
$post2=array( 
'e','f','g' ,'h' 
); 
$post['message'] = str_replace($post1, $post2, $post['message']);
$dataman->setr('pagetext', $post['message']); 


but that will only change new posts. To change existing posts in the database you would need to use SQL. You would probably want to do that once only (maybe by using phpMyAdmin), instead of making a plugin for it.