Rails - May 2006 - rubygems installation location

Hi

I just want to know where exactly gem should install. I had rails 
already installed in my system. I just installed gem package and tried 
to install a package through it. Unfortunately its prompting me to 
install rails also as dependency. I would also like to state that both 
rails and gem are installed on different locations.

Regards
Chetan Thapliyal