unpacked activerecord-oracle-adapter vs. system gem

I'm running into a problem using the oracle adapter when I have a
newer unpacked gem in vendor/gems and an old gem on the system. It
seems rails is failing with

** Starting Mongrel listening at 0.0.0.0:7654
** Starting Rails with development environment...
/usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:142:in `activate': can't
activate activerecord (>= 1.15.5.7843, runtime), already activated
activerecord-2.1.1 (Gem::Exception)
...

The problem seems to originate when the connection spec tries to load
the gem. Unfortunately it's not rescuing the proper exception. The
following seems to fix it for me. Has anyone else had a similar
problem? Thanks.

Cheers,
Flinn

--- lib/active_record/connection_adapters/abstract/
connection_specification.rb.orig 2008-09-19 14:57:37.000000000 -0400
+++ lib/active_record/connection_adapters/abstract/
connection_specification.rb 2008-09-19 14:59:18.000000000 -0400
@@ -225,7 +225,7 @@ module ActiveRecord
             require 'rubygems'
             gem "activerecord-#{spec[:adapter]}-adapter"
             require "active_record/connection_adapters/
#{spec[:adapter]}_adapter"
- rescue LoadError
+ rescue Gem::LoadError
             begin
               require "active_record/connection_adapters/
#{spec[:adapter]}_adapter"
             rescue LoadError