undefined method `alias_method_chain' for I18n::Backend::Simple:Class

Hi,

We are running RE:

ruby 1.8.7 (2009-06-12 patchlevel 174) [sparc-solaris2.10], MBARI 0x8770, Ruby Enterprise Edition 2009.10

I tried a simple web app with a controller rendering a text and is working in my PC but on the server I get:

Error message:     undefined method `alias_method_chain' for I18n::Backend::Simple:Class Exception class:     NoMethodError Application root:     /sites/rails-data/apps Backtrace:     # File Line Location     0 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/activerecord-2.3.4/ lib/active_record/i18n_interpolation_deprecation.rb 23     1 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `gem_original_require'     2 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `require'     3 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/activerecord-2.3.4/ lib/active_record.rb 83     4 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `gem_original_require'     5 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `require'     6 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 268 in `require_frameworks'     7 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 268 in `each'     8 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 268 in `require_frameworks'     9 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 134 in `process'     10 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 113 in `send'     11 /usr/ruby-enterprise/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/ initializer.rb 113 in `run'     12 /sites/rails-data/apps/config/environment.rb 9     13 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `gem_original_require'     14 /usr/ruby-enterprise/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb 31 in `require'

I had a look in activesupport-2.3.4/lib/active_support/vendor/ i18n-0.1.3/lib/i18n/backend/simple.rb and there is not any alias_method_chain method.

How can I solve this issue?

From the sys admin:

"It had updated the gem packages to start using 2.3.5 instead of 2.3.4 and the LD_LIBRAY_PATH variable was not set correctly."

This is how the problem has been solved.