Redirecting Wordpress posts with htaccess

I have a blog that uses Wordpress and accessing a post is done with the typical Wordpress URL:
http://www.maxprog.com/blog/?p=xxx

Now I want to redirect that to:
http://www.maxprog.com/site/blog/post.php?p=xxx

I am editing my site htaccess file. The following works perfects for posts:
RedirectMatch permanent ^/blog/(.*)$ /site/blog/post.php

However it also forward URLs where pictures are stored. So instead of going here:
http://www.maxprog.com/blog/wp-content/uploads/
it goes here:
http://www.maxprog.com/site/blog/wp-content/uploads/

Question is, how can I forward posts only? I have tried many things so far unsuccessfully.

RedirectMatch permanent ^/blog/?p=(.)$ /site/blog/post.php?id=$1
RedirectMatch permanent ^/blog/index.php?p=(.
)$ /site/blog/post.php?id=$1
RewriteRule ^blog/?p=(.)$ /site/blog/post.php?id=$1 [R=301,L]
RedirectMatch permanent ^/blog/?p=497$ /site/blog/post.php?id=497
RewriteRule ^/blog/(.
)$ /site/blog/post.php(.*) [R=301,L]
…etc…

Somebody has ever faced a similar issue? … else I will have to refresh my regex knowledge :-/

Stan

RedirectMatch permanent ^/blog/?(.*)$ /site/blog/post.php

Just include the question mark in the initial RegEx? You might need it after the “post.php” string as well…