Newbie having trouble with RubyGems

I am in the process of installing Ruby on Rails on AIX 5L 5.2. I was
unable to compile Ruby but successfully found a set of binaries for
AIX 5.1 which I deployed and tested. The Ruby tutorial I walked
through using these binaries worked flawlessly.

So I tired to install Gems using the ruby setup.rb command and I get
the following error:

<--- lib/rubygems/ digest <--- lib/ rubygems <--- lib /usr/local/ruby/lib/ruby/1.8/powerpc-aix5.1.0.0/digest/ load failed - /usr/local/ruby/lib/ruby/1.8/powerpc-aix5.1.0.0/digest/ (LoadError) from /usr/local/ruby/lib/ruby/site_ruby/1.8/rubygems/ custom_require.rb:27:in `require'

I am not familar with AIX (or any flavor of Unix for that matter) but
I need to get Ruby on Rails running in this environment if possible.

Any ideas on how to resolve the load failure on the object? Is
it because the binaries are for AIX 5.1 and I am running AIX 5.2?