Rewrite rule generating Internal Server Error

[eluser]TheFuzzy0ne[/eluser]
Did you try without the forward slash on the rewritten string (the string on the right)?

Code:

RewriteCond %{HTTP_HOST} !^www\.domain\.com [NC]
RewriteCond %{HTTP_HOST} ^([a-z0-9_-]+)\.domain\.com [NC]
RewriteRule ^/images/(.*)$ images/%1/$1 [L]