Ruby 1.9.0-0 RubyGems and environment variables ???

I do have installed install rb-appscript from svn (revision 436)
successfully for :
ruby 1.8.6 (2007-03-13 patchlevel 0) [powerpc-darwin8.9.0]

and

ruby 1.9.0 (2007-12-25 revision 14709) [powerpc-darwin8.11.0]

this version of rb-appscript has been tested from the developper itself, it
is well working on his computer with ruby 1.9.

but not on mine :[


notice that with the ruby 1.9 install i've added the suffix 19 (hence
ruby19, gem19 etc) and both are lying under /opt/local.



the simple script test :

----------------------------------------------------------------------
#! /usr/bin/env ruby19

#require "rubygems"
require "appscript"
include Appscript

p app('Finder').home.folders.get

----------------------------------------------------------------------

resulting in :

----------------------------------------------------------------------
RubyMate r6354 running Ruby r1.9.0 (/opt/local/bin/ruby19)
>>> desktop.rb

/opt/local/lib/ruby/site_ruby/1.8/_aem/aemreference.rb:15:in `new' : Not a
four-char-code string.  ( ArgumentError )
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/aemreference.rb:15:in
`pack_enum'
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/aemreference.rb:204:in
`<class:PositionSpecifier>'
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/aemreference.rb:193:in
`<module:AEMReference>'
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/aemreference.rb:44:in `<top
(required)>'
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/codecs.rb:8:in `require'
  from /opt/local/lib/ruby/site_ruby/1.8/_aem/codecs.rb:8:in `<top
(required)>'
  from /opt/local/lib/ruby/site_ruby/1.8/aem.rb:14:in `require'
  from /opt/local/lib/ruby/site_ruby/1.8/aem.rb:14:in `<module:AEM>'
  from /opt/local/lib/ruby/site_ruby/1.8/aem.rb:10:in `<top (required)>'
  from /opt/local/lib/ruby/site_ruby/1.8/appscript.rb:13:in `require'
  from /opt/local/lib/ruby/site_ruby/1.8/appscript.rb:13:in
`<module:Appscript>'
  from /opt/local/lib/ruby/site_ruby/1.8/appscript.rb:7:in `<top
(required)>'
  from /Users/yt/work/Ruby19/rb-appscript/Finder/desktop.rb:4:in `require'
  from /Users/yt/work/Ruby19/rb-appscript/Finder/desktop.rb:4:in `<main>'

----------------------------------------------------------------------

i suspect my environment variables are wrong for ruby19 :

export RUBYOPT=rubygems
export GEM_HOME=/opt/local/lib/ruby/gems/1.8
export
RUBYLIB=/opt/local/lib/ruby/:/opt/local/lib/ruby/site_ruby/1.8:/opt/local/lib/ruby/site_ruby/1.9.0
export RUBYGEMS=/opt/local/lib/ruby/site_ruby/1.8


is there somewhere a README to understand how ruby 1.9 (versus 1.8 ?) load
the libs ???

best,
-- 
yvon