Redmine

Hello to everyone!

I'm trying to install the easy_gantt plugin with this commands:

1) $ bundle install
 2) $ bundle exec rake db:migrate RAILS_ENV=production
 3) $ bundle exec rake redmine:plugins:migrate RAILS_ENV=production

but, after the command number 2, i'm getting this error:

Rails Error: Unable to access log file. Please ensure that /opt/bitnami/apps/redmine/htdocs/log/production.log exists and is writable (ie, make it writable for user and group: chmod 0664 /opt/bitnami/apps/redmine/htdocs/log/production.log). The log level has been raised to WARN and the output directed to STDERR until the problem is fixed.
rake aborted!
NoMethodError: private method `prepend' called for #<Class:0x007f56e0e4c440>
/opt/bitnami/apps/redmine/htdocs/config/environment.rb:14:in `<top (required)>'
Tasks: TOP => db:migrate => environment
(See full trace by running task with --trace)

This the informations about my redmine version:

Environment:
  Redmine version                3.2.0.stable
  Ruby version                   2.0.0-p647 (2015-08-18) [x86_64-linux]
  Rails version                  4.2.5
  Environment                    production
  Database adapter               Mysql2
SCM:
  Subversion                     1.8.13
  Cvs                            1.12.13
  Git                            2.6.1
  Filesystem                     
Redmine plugins:
  redmine_wktime                 2.1.2

How can i solve this problem? I really need to use this plugin...

Thank you a lot for your support.

Regards,
Salvatore La Rocca