Can't get even a simple Rails app to run? blocked by "“ERROR TypeError: can't dup NilClass”

"ERROR TypeError: can't dup NilClass" in a Rails 3 app? Any ideas -
I'm just hitting the home page and get this...it was working just
before...

Gregs-MacBook-Pro:test3 greg$ rails console
Loading development environment (Rails 3.2.1)

exit

Gregs-MacBook-Pro:test3 greg$ rails server
=> Booting WEBrick
=> Rails 3.2.1 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
[2012-02-13 09:19:59] INFO WEBrick 1.3.1
[2012-02-13 09:19:59] INFO ruby 1.8.7 (2010-01-10) [universal-
darwin11.0]
[2012-02-13 09:19:59] INFO WEBrick::HTTPServer#start: pid=8435
port=3000
[2012-02-13 09:20:27] ERROR TypeError: can't dup NilClass
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/httprequest.rb:204:in `dup'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/httprequest.rb:204:in `meta_vars'
        /Library/Ruby/Gems/1.8/gems/rack-1.4.1/lib/rack/handler/
webrick.rb:34:in `service'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/httpserver.rb:104:in `service'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/httpserver.rb:65:in `run'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:173:in `start_thread'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:162:in `start'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:162:in `start_thread'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:95:in `start'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:92:in `each'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:92:in `start'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:23:in `start'
        /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/
ruby/1.8/webrick/server.rb:82:in `start'
        /Library/Ruby/Gems/1.8/gems/rack-1.4.1/lib/rack/handler/
webrick.rb:13:in `run'
        /Library/Ruby/Gems/1.8/gems/rack-1.4.1/lib/rack/server.rb:
265:in `start'
        /Library/Ruby/Gems/1.8/gems/railties-3.2.1/lib/rails/commands/
server.rb:70:in `start'
        /Library/Ruby/Gems/1.8/gems/railties-3.2.1/lib/rails/
commands.rb:55
        /Library/Ruby/Gems/1.8/gems/railties-3.2.1/lib/rails/
commands.rb:50:in `tap'
        /Library/Ruby/Gems/1.8/gems/railties-3.2.1/lib/rails/
commands.rb:50
        script/rails:6:in `require'
        script/rails:6

Note that Ruby 1.8.7 p248 and p249 have marshaling bugs that crash
Rails 3.0. Ruby Enterprise Edition have these fixed since release
1.8.7-2010.02 though. On the 1.9 front, Ruby 1.9.1 is not usable
because it outright segfaults on Rails 3.0, so if you want to use
Rails 3 with 1.9.x jump on 1.9.2 for smooth sailing.

thanks - I'm deploying to http://dreamhost.com/ and they are on ruby
1.8.7 at the moment was the reason. Any comments here? Sounds like
it might be better assuming I'll have to do a custom ruby deployment
to the latest version on dreamhost perhaps? Their reply when I asked
the question about versions was:

oh dear,

Just when to latest ruby 1.9.3 using rvm, but I'm still getting same
error - basically can't use rails at all at the moment:

Gregs-MacBook-Pro:test_rvm193_1 greg$ ruby -v
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.3.0]
Gregs-MacBook-Pro:test_rvm193_1 greg$ which ruby
/Users/greg/.rvm/rubies/ruby-1.9.3-p0/bin/ruby
Gregs-MacBook-Pro:test_rvm193_1 greg$ rails -v
Rails 3.2.1
Gregs-MacBook-Pro:test_rvm193_1 greg$

Gregs-MacBook-Pro:test_rvm193_1 greg$ rails server
=> Booting WEBrick
=> Rails 3.2.1 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
[2012-02-13 11:30:11] INFO WEBrick 1.3.1
[2012-02-13 11:30:11] INFO ruby 1.9.3 (2011-10-30) [x86_64-
darwin11.3.0]
[2012-02-13 11:30:11] INFO WEBrick::HTTPServer#start: pid=36488
port=3000
[2012-02-13 11:30:32] ERROR TypeError: can't dup NilClass
        /Users/greg/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/
httprequest.rb:273:in `dup'
        /Users/greg/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/
httprequest.rb:273:in `meta_vars'
        /Users/greg/.rvm/gems/ruby-1.9.3-p0/gems/rack-1.4.1/lib/rack/
handler/webrick.rb:34:in `service'
        /Users/greg/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/
httpserver.rb:138:in `service'
        /Users/greg/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/
httpserver.rb:94:in `run'
        /Users/greg/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/
server.rb:191:in `block in start_thread'
^C[2012-02-13 11:31:04] INFO going to shutdown ...

Any ideas?

arrr - I noted I had "https" not "http" in the url I was calling.
That is I was using "https://localhost:3000". Should this have had
such an effect on rails?