Try downloading the rails 1.1.6 tgz from the rubyforge download page,
extract the contents and copy the extracted vendor/rails directory to
your project's RAILS_ROOT/vendor/ directory, this should overwrite the
installed gem version with the rails version in your vendor directory
(aka 1.1.6)
ie.
dir (or ls, etc) RAILS_ROOT/vendor/
(should result in)
.. rails/
.. plugins/
then:
dir RAILS_ROOT/vendor/rails/
(should result in)
.. actionmailer/
.. actionpack/
.. activerecord/
.. etc.
Ciao
Gustav Paul