On my website, all images/stylesheets are in the /CMS/... directory. Recently, our website shifted to new server at a temporary url where they referenced like /newdirecto
I'd suggest using mod_rewrite, which most apache/linux servers have. Create a file called .htaccess in the docroot of your site with the contents:
RewriteEngine On
RewriteBase /
RewriteRule ^/CMS/(.*)$ /newdirectory/CMS/$1 [QSA]
This method will make it transparent to the end user and no impact on current pagerank, SEO, etc value and all inbound links will be maintained.