I regularly install Ruby from source on CentOS hosts, and if there was going to be a problem it'd be there.
Ruby 1.9+ installs easily. Typically I'll install a standard Ruby using a distribution for Centos, which loads all the prerequisites, then will install 1.9+ into /usr/local/bin using the standard make
.
Otherwise, since you've used RVM, ask it what prerequisites you need, then install them from your package manager, and compile Ruby from source.
Here's a little shell script I wrote to speed up the process for some of our boxes:
#!/bin/sh
echo "Installing Ruby's prerequisites"
sudo yum install -y gcc-c++ patch readline-devel readline zlib-devel zlib libyaml-devel libffi-devel openssl-devel iconv-devel
echo "Installing Nokogiri's prerequisites"
sudo yum install -y ruby-devel libxml2-devel libxml2 libxslt-devel libxslt
echo "Installing MySQL/Sequel's development prerequisites"
sudo yum install -y mysql-devel freetds-devel freetds
echo "Now install Ruby from http://www.ruby-lang.org/en/downloads/ then run..."
echo sudo gem install \
amqp \
awesome_print \
bunny \
colors \
columnize \
debugger \
highline \
ipaddress \
irbtools \
mysql2 \
net-scp \
net-sftp \
net-ssh \
netaddr \
nokogiri \
pry \
rails \
sequel \
sinatra \
tiny_tds \