Rails 1.2.3 application

I have an existing Ruby application built on Rails 1.2.3.
I'm trying to find an environment with an IDE that I can use to
upgrade the application to a newer version.

1. I chose RadRails, which at the moment requires Ruby 1.8, so I
installed 1.8.6-i386-mingw32.
On top of that I added Rails 2.3.5, expecting that would be the best
target version.
I removed the requirement for the app to run against 1.2.3 from the
environment.rb file and ran the server.
After fixing a couple of initial incompatibilities in the environments
files, I get this error when I try to render the default view:
<%= text_field_tag 'login' %>
wrong number of arguments (2 for 1)
C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.5/lib/action_view/
helpers/tag_helper.rb:41:in `tag_options'
C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.5/lib/action_view/
helpers/tag_helper.rb:41:in `tag'
C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.5/lib/action_view/
helpers/form_tag_helper.rb:115:in `text_field_tag'
Digging around, I found that the error seems to be *inside Rails*.

2. Instead I decided to install Rails 1.2.3 and see if it would work
with Ruby 1.8.6.
I added back in the RAILS_GEM_VERSION line in the environment.rb file
and tried again, this time getting:
C:/Ruby/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/initializer.rb:328:in
`send': und
efined method `session=' for ActionController::Base:Class
(NoMethodError)
during the initialization.
Perhaps a compatibility issue between the version of Mongrel I have
installed and Rails 1.2.3? Just a shot in the dark.

Any help would be appreciated!

d:\projects\rcx>gem list --local

*** LOCAL GEMS ***

actionmailer (2.3.5, 1.3.3)
actionpack (2.3.5, 1.13.3)
actionwebservice (1.2.3)
activerecord (2.3.5, 1.15.3)
activeresource (2.3.5)
activesupport (2.3.5, 1.4.2)
cgi_multipart_eof_fix (2.5.0)
fastthread (1.0.1)
gem_plugin (0.2.3)
httpclient (2.1.5.2)
linecache (0.43)
mongrel (1.1.5)
mysql (2.8.1.1)
rack (1.1.0, 1.0.1)
rails (2.3.5, 1.2.3)
rake (0.8.7)
ruby-debug-base (0.10.3)
ruby-debug-ide (0.4.5)
soap4r (1.5.8)
sqlite3-ruby (1.2.5, 1.2.1)
tzinfo (0.3.16, 0.3.15)

d:\projects\rcx>ruby -v
ruby 1.8.6 (2009-08-04 patchlevel 383) [i386-mingw32]

d:\projects\rcx>rails -v
Rails 2.3.5

d:\projects\rcx>gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 1.3.5
  - RUBY VERSION: 1.8.6 (2009-08-04 patchlevel 383) [i386-mingw32]
  - INSTALLATION DIRECTORY: C:/Ruby/lib/ruby/gems/1.8
  - RUBY EXECUTABLE: C:/Ruby/bin/ruby.exe
  - EXECUTABLE DIRECTORY: C:/Ruby/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86-mingw32
  - GEM PATHS:
     - C:/Ruby/lib/ruby/gems/1.8
     - C:/Users/Andrews/.gem/ruby/1.8
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
  - REMOTE SOURCES:
     - http://gems.rubyforge.org/

Hi k00ka,

This list is for Ruby on Rails Core issues. If you would like help with general Ruby on Rails help please visit the rubyonrails-talk mailing list, or the #rubyonrails channel on irc.freenode.net.

Thanks,

Ryan