400 error in log files

Hi,

I got http://www.strictlyreading.co.uk which I can view fine and so can others. Using the sitemap plugin, I can navigate the site fine and create a sitemap fine (apart from http://www.strictlyreading.co.uk/reading2006/ for some reason)

Anyway, when I try to submit the page to Yahoo or use something like phpSitemapNG to index the site, nothing happens and when I check the logs I get somethin simiar to:

89.145.66.200 - - [09/Nov/2006:10:10:56 +0000] "GET / HTTP/1.1" 400 922 "http://strictlyreading.co.uk/" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; phpSitemapNG 1.5.3)"

206.190.57.40 - - [09/Nov/2006:10:08:47 +0000] "GET /reading2006/ HTTP/1.0" 400 908 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows 98)"

Any reason for this to happen? I need to index the whole site (including the reading2006 page that uses a flickr plugin) and submit it to several search engines.

Thanks!