ActiveResource 2.3.4 produces warnings about uninitialized instance variables

Using ActiveResource 2.3.4 in a standalone mode (i.e., not in a Rails project), I get the following warnings:

/Library/Ruby/Gems/1.8/gems/activeresource-2.3.4/lib/active_resource/connection.rb:219: warning: instance variable @proxy not initialized /Library/Ruby/Gems/1.8/gems/activeresource-2.3.4/lib/active_resource/connection.rb:230: warning: instance variable @timeout not initialized

I did set a user and password, but not timeout and not proxy.