tedster - 7:08 pm on Dec 23, 2011 (gmt 0)
It is crawling them because they are in the sitemap. For some reason the sitemap file contains entries like this:
< loc >http://www.example.co.uk/show_s< /loc >
I'd say getting those files out of the sitemap is your first order of business. Something isn't right in your sitemap generation.