undefined method after freezing rails

Hi,

i've upgraded my rails version to 1.2.1 Cause i've some application build with version 1.1.6, i've frozen their version using rake rails:freeze:edge TAG=rev_1.1.6

But now i'm getting an error, if i try to start webbrick. I've tried to include time class by adding require 'time' to environment.rb, but this doesn't help.

/usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:92:in `load_specification': undefined method `parse' for Time:Class (NoMethodError)         from /usr/local/lib/site_ruby/1.8/rubygems/specification.rb:314:in `date='         from /usr/local/lib/site_ruby/1.8/rubygems/specification.rb:416:in `initialize'         from /usr/local/lib/site_ruby/1.8/rubygems/specification.rb:412:in `initialize'         from (eval):1:in `load_specification'         from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:128:in `eval'         from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:92:in `load_specification'         from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:128:in `load_gems_in'         from /usr/local/lib/site_ruby/1.8/rubygems/source_index.rb:127:in `load_gems_in'          ... 24 levels...         from ./script/../config/../vendor/rails/railties/lib/commands/servers/webrick.rb:52         from ./script/../config/../vendor/rails/activesupport/lib/active_support/dependencies.rb:147:in `require'         from ./script/../config/../vendor/rails/railties/lib/commands/server.rb:30         from ./script/server:3

Any ideas how to get rid of this error?

greeting Phil

Are you using the Icalendar gem?

-faisal