Domain change; how to set up htaccess redirect for files?

I am not sure whether this belongs in Software or in some other forum, but I'm sure a mod will move it where it belongs if I got it wrong...

I am moving a blog from domain A to domain B. I would like to modify the .htaccess so that if someone goes to olddomain/blog/post8.php, they'll be redirected to newdomain/blog/post8.php, without me having to set this up for each post separately. There should be a way to do it with htaccess.

I've already set up a wildcard redirection through cPanel for the domain, but that just takes any address under the old domain into the root of the new one...

Thanks for any possible help.

Try this in the .htaccess file:
Haven't tried it, but it should work.