Ruby on Rails

Hi all,

i have a strange problem on a system which i'm not administrating but deploying to.
After Capistrano fails i tried to install an gem manually an got that error i can't not reproduce on my testing system.
Can anyone give me an hint where i have to search to get that problem fixed?
Which information do i have to provide to you to give a better picture what is happening?

gem --backtrace install gyoku -V '1.1.1'
ERROR:  While executing gem ... (NoMethodError)
    undefined method `extensions' for nil:NilClass
        /DBA/ruby/1.9.3-p484/lib/ruby/1.9.1/openssl/ssl-internal.rb:93:in `verify_certificate_identity'
        /DBA/ruby/1.9.3-p484/lib/ruby/1.9.1/openssl/ssl-internal.rb:133:in `post_connection_check'
        /DBA/ruby/1.9.3-p484/lib/ruby/1.9.1/net/http.rb:802:in `connect'
        /DBA/ruby/1.9.3-p484/lib/ruby/1.9.1/net/http.rb:756:in `do_start'
        /DBA/ruby/1.9.3-p484/lib/ruby/1.9.1/net/http.rb:751:in `start'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request/http_pool.rb:33:in `setup_connection'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request/https_pool.rb:6:in `setup_connection'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request/http_pool.rb:29:in `make_connection'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request/http_pool.rb:19:in `checkout'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request.rb:85:in `connection_for'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request.rb:140:in `perform_request'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/request.rb:109:in `fetch'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/remote_fetcher.rb:346:in `request'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/remote_fetcher.rb:231:in `fetch_http'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/remote_fetcher.rb:247:in `fetch_http'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/remote_fetcher.rb:267:in `fetch_path'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/source.rb:148:in `fetch_spec'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/resolver/api_specification.rb:76:in `spec'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/resolver/installer_set.rb:77:in `add_always_install'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/dependency_installer.rb:463:in `resolve_dependencies'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/commands/install_command.rb:238:in `install_gem'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/commands/install_command.rb:299:in `block in install_gems'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/commands/install_command.rb:295:in `each'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/commands/install_command.rb:295:in `install_gems'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/commands/install_command.rb:202:in `execute'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/command.rb:307:in `invoke_with_build_args'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/command_manager.rb:168:in `process_args'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/command_manager.rb:138:in `run'
        /DBA/ruby/1.9.3-p484/lib/ruby/site_ruby/1.9.1/rubygems/gem_runner.rb:54:in `run'
        /DBA/ruby/1.9.3-p484/bin/gem:21:in `<main>'

Many thanks,
Marco