If you have tried to install Mechanize or any gem that requires openssl on Ubuntu or Debian, you may have encountered the following error…

LoadError: no such file to load—openssl

despite the fact that you have installed openssl with “gem install libopenssl-ruby”.

Thanks to this thread, I found out that in order to install openssl, you have to tell ruby how to compile the openssl extension, like this…

cd /ruby-1.8.4/ext/openssl
ruby extconf.rb
make

Source: http://www.jessirae.com/blog/articles/2007/03/11/installing-openssl-on-ubuntu
make install