RewriteRule variables blank

Question

I have a couple of rewrite rules in htaccess. They work on one server but not another. My script is as follows (I've commented out how the urls look):

RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_URI} !^/images/

#example.com/regions/fife/
RewriteRule ^regions/([A-Za-z0-9\-\+\']+)/?$ /regions.php?region=$1 [L]

#example.com/regions/fife/dunfermline
RewriteRule ^regions/([^/]+)/([^/]+)$ /regions.php?region=$1&town=$2 [L] 

It returns two variables (region & town) I can manipulate in PHP, and throw up the appropriate content. I have a Rackspace server, and the script works perfectly, but on another server (Freedom2surf) it only works so far. It doesn't return the variables. I get a blank $_GET array...

Any ideas? F2S aren't giving me any clues, just that I should check my code. But if it works on another server, then what gives? Is it an Apache setting that is different?