Redmine

Hi community, during redmine installation (Debian) generates the following error:

rake db:migrate RAILS_ENV='production' --trace

rake aborted!
no such file to load -- rexml/encodings/UTF-8.rb
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/usr/local/lib/ruby/1.8/rexml/encoding.rb:48:in `old_enc='
/usr/local/lib/ruby/1.8/rexml/xmldecl.rb:79:in `encoding='
/usr/local/lib/ruby/1.8/rexml/xmldecl.rb:30:in `initialize'
/usr/local/lib/ruby/1.8/rexml/xmldecl.rb:94:in `new'
/usr/local/lib/ruby/1.8/rexml/xmldecl.rb:94:in `default'
/usr/local/lib/ruby/1.8/rexml/document.rb:25
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/vendor/xml-simple-1.0.11/xmlsimple.rb:7
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext/hash/conversions.rb:4
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext/hash.rb:2
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext/hash.rb:1:in `each'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext/hash.rb:1
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext.rb:3
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext.rb:1:in `each'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support/core_ext.rb:1
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/activesupport/lib/active_support.rb:31
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/railties/lib/tasks/misc.rake:12
/var/www/rails_apps/redmine-0.8.4/vendor/rails/railties/lib/tasks/rails.rb:4:in `load'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/railties/lib/tasks/rails.rb:4
/var/www/rails_apps/redmine-0.8.4/vendor/rails/railties/lib/tasks/rails.rb:4:in `each'
/var/www/rails_apps/redmine-0.8.4/vendor/rails/railties/lib/tasks/rails.rb:4
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require'
/usr/local/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
/var/www/rails_apps/redmine-0.8.4/Rakefile:10
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2383:in `load'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2383:in `raw_load_rakefile'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2017:in `load_rakefile'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2016:in `load_rakefile'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2000:in `run'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
/usr/local/lib/ruby/gems/1.8/gems/rake-0.8.7/bin/rake:31
/usr/local/bin/rake:19:in `load'
/usr/local/bin/rake:19

My database.yml:

production:
adapter: postgresql
database: redmine
host: localhost
username: redmine
password: redmine
encoding: utf8

Appreciate the help.