How to configure Log4r with Rails 3.0.x?

I tried configuring log4r with Rails 3.0.4 based on this article: http://www.dansketcher.com/2007/06/16/integrating-log4r-and-ruby-on-rails/

/Users/toto/.rvm/gems/ruby-1.9.2-p0/gems/log4r-1.1.9/lib/log4r/yamlconfigurator.rb:166:in `sub!': can't convert Pathname into String (TypeError)
    from /Users/toto/.rvm/gems/ruby-1.9.2-p0/gems/log4r-1.1.9/lib/log4r/yamlconfigurator.rb:166:in `block in paramsub'
    from /Users/toto/.rvm/gems/ruby-1.9.2-p0/gems/log4r-1.1.9/lib/log4r/yamlconfigurator.rb:165:in `each'
    from /Users/toto/.rvm/gems/ruby-1.9.2-p0/gems/log4r-1.1.9/lib/log4r/yamlconfigurator.rb:165:in `paramsub'
    from /Users/toto/.rvm/gems/ruby-1.9.2-p0/gems/log4r-1.1.9/lib/log4r/yamlconfigurator.rb:156:in `block in decode_hash_params'

I have Googled for a Rails 3 integration, but have not found a working solution. Can anyone point me to a working code snippet that will allow log configuration using a YAML file, and initialization at runtime?

Just as a reference, I placed the sample logger.rb in the config/initializers folder and the log4r.yml in the config directory.

Thanks