Rails - Aug 2006 - Ajax request containing special characters

Hello !
  Fooling around with Rails, I came accross a strang thing which I think
is a bug : when an Ajax request is sent with an observer, the content of the
field is sent directly in post, and is then parsed by CGI::parse.
  If the field content starts with ''&'' and then another
character, let''s
say ''a'', CGI::parse set @params with {nil => [nil],
"a" => [nil]}.
  Rails then fails with the following backtrace :

You have a nil object when you didn''t expect it!
You might have expected an instance of Array.
The error occured while evaluating nil.include?
./script/../config/../vendor/rails/actionpack/lib/action_controller/cgi_ext/cgi_methods.rb:49:in
`parse_request_parameters''
./script/../config/../vendor/rails/actionpack/lib/action_controller/cgi_ext/cgi_methods.rb:47:in
`parse_request_parameters''
./script/../config/../vendor/rails/actionpack/lib/action_controller/cgi_process.rb:71:in
`request_parameters''
./script/../config/../vendor/rails/actionpack/lib/action_controller/request.rb:13:in
`parameters''
./script/../config/../vendor/rails/actionpack/lib/action_controller/session_management.rb:122:in
`set_session_options_without_components''
./script/../config/../vendor/rails/actionpack/lib/action_controller/components.rb:178:in
`set_session_options''
./script/../config/../vendor/rails/actionpack/lib/action_controller/session_management.rb:116:in
`process''
./script/../config/../vendor/rails/railties/lib/dispatcher.rb:38:in
`dispatch''
./script/../config/../vendor/rails/railties/lib/webrick_server.rb:115:in
`handle_dispatch''
./script/../config/../vendor/rails/railties/lib/webrick_server.rb:81:in
`service''
/usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service''
/usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run''
/usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread''
/usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread''
/usr/lib/ruby/1.8/webrick/server.rb:95:in `start''
/usr/lib/ruby/1.8/webrick/server.rb:92:in `start''
/usr/lib/ruby/1.8/webrick/server.rb:23:in `start''
/usr/lib/ruby/1.8/webrick/server.rb:82:in `start''
/usr/lib/ruby/1.8/webrick/server.rb:23:in `start''^M
/usr/lib/ruby/1.8/webrick/server.rb:82:in `start''^M
./script/../config/../vendor/rails/railties/lib/webrick_server.rb:67:in
`dispatc\h''
./script/../config/../vendor/rails/railties/lib/commands/servers/webrick.rb:59^M/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in
`require''
./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies\.rb:147:in
`require''
./script/../config/../vendor/rails/railties/lib/commands/server.rb:30
script/server:3

  Should observe_field method escape special characters?
  Thanks for your help.

-- 
Jean-Philippe Garcia Ballester