How to make octopress use system version of ruby

How to make octopress use system version of ruby

I am trying to setup octopress on my mac. The default version of ruby on
my mac was 1.8.7 but I have upgraded it to 2.0.0. If I do
'which ruby'
it prints
'/Users/liqiushi/.rvm/rubies/ruby-2.0.0-p247/bin/ruby'.
After cloning my existed sources from github and 'cd' into that folder, I
got the following error:
'You are using '.rvmrc', it requires trusting, it is slower and it is not
compatible with other ruby managers, you can switch to '.ruby-version'
using 'rvm rvmrc to [.]ruby-version' or ignore this warning with 'rvm
rvmrc warning ignore
/Users/liqiushi/Documents/photosynthesiis.github.com/.rvmrc', '.rvmrc'
will continue to be the default project file in RVM 1 and RVM 2, to ignore
the warning for all files run 'rvm rvmrc warning ignore all.rvmrcs'.
ruby-1.9.3-p448 is not installed. To install do: 'rvm install
ruby-1.9.3-p448''
if I do
'ruby -v'
in the octopress folder it prints
'ruby 1.8.7 (2012-02-08 patchlevel 358) [universal-darwin12.0]'
, and if I do
'which ruby'
it prints
'/usr/bin/ruby'
Can anyone tell how to make octopress to use ruby I just upgraded in my
mac instead of using 1.8.7. thanks