Setting up IIRF to redirect to www

So I have been doing some testing on my website and needed to redirect requests to http://chrishammond.com to http://www.chrishammond.com/. Lucky for me the site is using IIRF to manage my urls from the old community server days to my DotNetNuke conversion.

Using IIRF I'm able to create a simple rule that will handle the redirects for me, I've pasted it below.

# force proper www. prefix on all requests
RewriteCond %{HTTP_HOST} ^chrishammond\.com [I]
RewriteRule ^/(.*) http://www.chrishammond.com/$1 [I,RP]