OS X After 1.9 Upgrade I get common errors in ri, gem, etc

Around the first of the year I upgraded my OS X 10.5 laptop to Ruby 1.9.
I just used the default procedure:
$ autoconf
$ ./configure
$ make
$ make install

I did not use the --prefix option for ./configure. I now have two Ruby
builds:
/usr/bin/ruby (1.8.6 came with OS X)
/usr/local/bin/ruby (1.9 just installed, this is the default if I just
type ruby in the terminal)

However if I try to run ri (which runs /usr/local/bin/ri) I get the
following error:
joe[~]$ ri
/usr/local/lib/ruby/1.9.0/yaml.rb:9:in require': no such file to load -- stringio (LoadError) from /usr/local/lib/ruby/1.9.0/yaml.rb:9:in<top (required)>’
from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_descriptions.rb:1:in
require' from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_descriptions.rb:1:in<top
(required)>’
from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_reader.rb:1:in
require' from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_reader.rb:1:in<top
(required)>’
from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_driver.rb:5:in
require' from /usr/local/lib/ruby/1.9.0/rdoc/ri/ri_driver.rb:5:in<top
(required)>’
from /usr/local/bin/ri:43:in require' from /usr/local/bin/ri:43:in

I can still resort to the 1.8.6 version of ri in /usr/bin/ri but it is
discouraging to have to use 1.8.6 after just installing 1.9. I have the
same issue with gem:
joe[~]$ gem
/usr/local/lib/ruby/1.9.0/yaml.rb:9:in require': no such file to load -- stringio (LoadError) from /usr/local/lib/ruby/1.9.0/yaml.rb:9:in<top (required)>’
from /usr/local/lib/ruby/1.9.0/rubygems/config_file.rb:7:in
require' from /usr/local/lib/ruby/1.9.0/rubygems/config_file.rb:7:in<top (required)>’
from /usr/local/lib/ruby/1.9.0/rubygems/gem_runner.rb:8:in
require' from /usr/local/lib/ruby/1.9.0/rubygems/gem_runner.rb:8:in<top (required)>’
from /usr/local/bin/gem:9:in require' from /usr/local/bin/gem:9:in

Is there an easy fix to the problem or if I reinstall 1.9 using --prefix
option will it be any different?

Thanks In Advance!!
Joseph P.