I'm having trouble with a Apache Rewrite rule that needs to pass two variables. It should be simple enough, but the output is not parsing the variable properly.

Here's the rule as I'm using it:
RewriteRule ^/?(category)/([A-Za-z-]+)/([0-9-]+)/?$ /index.php?c=$2&start=$3 [L]

essentially, the input would be: http://www.example.com/category/dogs/2

which should internally be http://www.example.com/index.php?c=dogs&start=2

instead, what i get is http://www.example.com/index.php?c=dogs/2&start=

why are $2 and $3 not parsing?

Thanks in advance...