Rails or separate packages, RedHat

So, as I introduced myself to ActiveRecord, I asked our IT department
to install activerecord and this hierarchy popped up on the system:

then I was able to do this
irb(main):003:0> require 'rubygems'
=> true
irb(main):004:0> require 'activerecord'
=> true

Now I realize FasterCSV, and perhaps migrations would be handy. I'm
not building a web application at the moment, rather I'm building a
command line api to our DB using ActiveRecord for ORM. However
perhaps one day in the future I'll be allowed a rails developed web

So, do I ask the IT department to install Ruby on Rails or continue
asking for particular packages? I'd rather just get the whole thing.
If so, will an install of "rails" override or interfere with already
installed rails libraries? They will only install RedHat 5 managed
packages without a huge fight. Other packages, I have to compile and
install in my own user space (/home).

This is on a RedHat RHEL 5 system (uname = 2.6.18-128.1.1.el5).

Cheers and thanks!

Good point. Ok, a dumb question.

I found I can run "gem install -i install_dir -d bin_dir"

Where do people usually install such things in their user spaces?

What about the "-d bin_dir"? What kind of things go in there? .so
libraries like mysql.so? What default location do those usually end
up in? Where is a usual place to put them in my home space?

What environment variables do I need to work with to make my installed
gems are used instead of older system installed gems?



If you install the gems as a non root user it will be installed in

gem install rails

will install it in ~/.gems

I tried that and this is what happened. The system Ruby is 1.8.7.

[~/] gem install rails
ERROR: While executing gem ... (Errno::EACCES)
    Permission denied - /var/lib/gems/1.8/cache/rake-0.8.4.gem