Redmine

Hi,
I'm upgrading the redmine from 2.3.1 to 2.5.0. After the upgrade the POST request via REST API is not working. It returns
Filter chain halted as :verify_authenticity_token rendered or redirected.
Here is my log.

Started POST "/redmine/projects/1/issues" for 10.164.37.53 at 2014-04-01 16:06:01 +0800
Processing by IssuesController#create as HTML
  Parameters: {"issue"=>{"project_id"=>1, "tracker_id"=>1, "subject"=>"test2", "status_id"=>1, "priority_id"=>2}, "project_id"=>"1"}
WARNING: Can't verify CSRF token authenticity
  Rendered common/error.html.erb within layouts/base (0.2ms)
Filter chain halted as :verify_authenticity_token rendered or redirected
Completed 422 Unprocessable Entity in 7.4ms (Views: 7.0ms | ActiveRecord: 0.0ms)

2.3.1

Environment:
  Redmine version                          2.3.1.stable
  Ruby version                             1.9.3 (x86_64-linux)
  Rails version                            3.2.13
  Environment                              production
  Database adapter                         Mysql2
Redmine plugins:
  no plugin installed

2.5.0

Environment:
  Redmine version                2.5.0.stable
  Ruby version                   1.9.3-p545 (2014-02-24) [x86_64-linux]
  Rails version                  3.2.17
  Environment                    production
  Database adapter               Mysql2
SCM:
  Subversion                     1.8.5
  Git                            1.8.5.2
  Filesystem                     
Redmine plugins:
  no plugin installed