Redmine

Hello guys, this is my first post here.
My Redmine is taking more than 3 minutes (yes, minutes!) to update or save any task.
During this wait, my server do not uses more memory or cpu than normal.

SO: Ubuntu 11.04
About your application's environment
Ruby version 1.8.7 (x86_64-linux)
RubyGems version 1.8.10
Rack version 1.1.2
Rails version 2.3.12
Active Record version 2.3.12
Active Resource version 2.3.12
Action Mailer version 2.3.12
Active Support version 2.3.12
Application root /var/rails_app/projetos
Environment production
Database adapter mysql
Database schema version 20111209015056

About your Redmine plugins
Redmine Opensearch plugin 0.1
Issue from message plugin 0.0.4
Redmine Time Tracker plugin 0.4
Redmine Question plugin 0.3.0
Redmine Light Box plugin 0.0.1
Redmine Notifo plugin 0.1.0
Redmine Extended Spent Time plugin 0.0.2
Redmine JChat 0.2.0
Redmine GSC My Projects plugin 0.0.2
Redmine Better Gantt Chart plugin 0.5.3
Redmine Task List plugin 0.0.1
Rate 0.2.1
Redmine Close Button plugin 0.0.3
Redmine Auto Done 100% 0.0.1
Customer plugin 0.2.0
Stuff To Do Plugin 0.4.0

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