Win7,ruby1.9.2p136. gem install rails not working

Rails
1

Hello!
I cannot install rails. gem install rails returns:

ERROR: While executing gem … (TypeError)
incompatible marshal file format (can’t be read)
format version 4.8 required; 0.0 given

Interpreter is installed from http://rubyinstaller.org/ .
Fresh installation, gem list --local returns:

*** LOCAL GEMS ***

minitest (1.6.0)
rake (0.8.7)
rdoc (2.5.8)

gem env returns:

RubyGems Environment:

  • RUBYGEMS VERSION: 1.3.7
  • RUBY VERSION: 1.9.2 (2010-12-25 patchlevel 136) [i386-mingw32]
  • INSTALLATION DIRECTORY: C:/Ruby192/lib/ruby/gems/1.9.1
  • RUBY EXECUTABLE: C:/Ruby192/bin/ruby.exe
  • EXECUTABLE DIRECTORY: C:/Ruby192/bin
  • RUBYGEMS PLATFORMS:
    • ruby
    • x86-mingw32
  • GEM PATHS:
    • C:/Ruby192/lib/ruby/gems/1.9.1
    • C:/Users/user/.gem/ruby/1.9.1
  • GEM CONFIGURATION:
    • :update_sources => true
    • :verbose => true
    • :benchmark => false
    • :backtrace => false
    • :bulk_threshold => 1000
    • :sources => [“http://rubygems.org/”]
  • REMOTE SOURCES:

Is there any workaround that I can try? Thanks in advance.