redirect subdomain to append to uri

I've been using the below code flawlessly for a couple of years now (funny, I found this post again from Google searching). I could now use an update if someone would be so kind: I need to check and remove if someone has www. in front of the subdomain intended. Using my original example:

 

 

greg.domain.com --> www.domain.com/sites/greg

 

bob.domain.dom --> www.domain.com/sites/bob

 

www.greg.domain.com --> www.domain.com/sites/greg

 

www.bob.domain.com --> www.domain.com/sites/bob

 

 

when HTTP_REQUEST {

 

Check for a non-null length host header

 

if {[string match {*[a-zA-Z]*} [HTTP::host]]}{

 

Use the getfield command to parse the subdomain

 

set subdomain [getfield [HTTP::host] . 1]

 

HTTP::redirect http://www.domain.com/sites/$subdomain

 

}

 

}

 

 

Any help appreciated! Thanks!