Rails - Nov 2005 - Dispatch error on textdrive

Any ideas what coule be causing this error when I run dispatch.cgi?

xxx@gilford$ ./dispatch.cgi
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/request.rb:13:in
`method'': undefined method `downcase'' for nil:NilClass
(NoMethodError)
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/request.rb:23:in
`post?''
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/request.rb:68:in
`formatted_post?''
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/cgi_process.rb:66:in
`request_parameters''
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/request.rb:8:in
`parameters''
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/session_management.rb:114:in
`process''
        from 
/usr/local/lib/ruby/gems/1.8/gems/actionpack-1.10.2/lib/action_controller/rescue.rb:20:in
`process_with_exception''
        from 
/usr/local/lib/ruby/gems/1.8/gems/rails-0.14.2/lib/dispatcher.rb:38:in 
`dispatch''
        from ./dispatch.cgi:10


The site was working fine previously, but is now giving out these 
errors. Other sites on the same box seem to be fine.

Thanks in advance.

-- 
R.Livsey
http://livsey.org