uninitialized constant ActiveSupport::Dependencies::Mutex (NameError)

I’m on debian etch w/ ruby1.8, activesupport-2.3.2, getting this on the first line of code which is require ‘active_support’ :

/var/lib/gems/1.8/gems/activesupport-2.3.2/lib/active_support/dependencies.rb:55: uninitialized constant ActiveSupport::Dependencies::Mutex (NameError)

from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require'
from /var/lib/gems/1.8/gems/activesupport-2.3.2/lib/active_support.rb:56

from /usr/lib/ruby/1.8/rubygems/custom_require.rb:33:in `gem_original_require'
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:33:in `require'

Note that this worked as expected on ubuntu (ibix, amd64).

Thanks,

m

I had the same issue after upgrading rails to 2.3.2 on a Debian
machine. Updating the rubygems package (apt-get install rubygems)
fixed it.