[brighter]

What do you mean by that? Reconfigure what?!

The application was correctly configured before the migration took place. Since the migration, I've edited the dispatch.fcgi file to refer to the correct location of ruby (before a, let me check... Reboot at 1am.. That wasn't scheduled! ... symlink was added at half past 8, at which point I changed it back).

The handlers are still set in htaccess. The browser renders disptach.fcgi as plain text, it does not execute it.

My app now starts Webrick rather than Mongrel. mongrel_rails start does the following:

# mongrel_rails start  
/usr/lib/ruby/site_ruby/1.8/rubygems.rb:304:in `report_activate_error': Could not find RubyGem mongrel (>= 0) (Gem::LoadError)
        from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:238:in `activate'
        from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:76:in `active_gem_with_options'
        from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:50:in `gem'

The cpanel "Show Available Ruby Gem(s)" button (RubyGem option) returns "There was a problem fetching the list of available modules."

Attempting to install a gem via console:

# gem install mongrel
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require': no such file to load -- sources (LoadError)
        from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
        from /usr/lib/ruby/site_ruby/1.8/rubygems/source_info_cache.rb:6
        from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
        from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
        from /usr/lib/ruby/site_ruby/1.8/rubygems/remote_installer.rb:12
        from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
        from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
        from /usr/lib/ruby/site_ruby/1.8/rubygems.rb:112:in `manage_gems'
        from /usr/local/bin/gem:12