Ajax problem with rails 2.0.2 - frozen string?

I am deploying a new rails application on a shared host (hostingrails)
for the first time. My local app works great. However, Ajax requests
in the deployed application are generating the following error:

/!\ FAILSAFE /!\ Fri Feb 15 08:44:59 -0600 2008
  Status: 500 Internal Server Error
  can't modify frozen string
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:462:in `gsub!'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:462:in `clean_up_ajax_request_body!'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:380:in
`parse_formatted_request_parameters'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/cgi_process.rb:78:in `request_parameters'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:287:in `parameters'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:22:in `request_method'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/request.rb:35:in `method'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/routing.rb:1483:in `extract_request_environment'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/routing.rb:1424:in `recognize'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/dispatcher.rb:170:in `handle_request'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/dispatcher.rb:115:in `dispatch'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/dispatcher.rb:126:in `dispatch_cgi'
    /usr/local/lib/ruby/gems/1.8/gems/actionpack-2.0.2/lib/
action_controller/dispatcher.rb:9:in `dispatch'
    dispatch.cgi:10

Any help here would be great!

This seems to be FastCGI specific. The problem is gone on Mongrel.

have the same problem on site5

I have the same issue on my ASO hosting. More and more I realize that
if your gonna host an RoR site, shared hosting is not the way to go.