well, I tried it on vb4.2 pl3, but not changes noticed!!
I know what better solution is, you can re-arrange your external css and js files in a certain order where css files have to be always on top and then js files after. you will notice sharp changes. You also need to add header set like this one:
Code:
<IfModule mod_headers.c>
<FilesMatch "\.(bmp|css|flv|gif|ico|jpg|jpeg|js|pdf|png|svg|swf|tif|tiff)$">
Header set Last-Modified "Mon, 31 Jan 2013 00:00:00 GMT"
</FilesMatch>
</IfModule>
just copy exact code and no worries. place that code in the .htaccess in the same forum root...
Good luck.