In file jdbc_adapter.rb,the following method adds the bind variable where pk will be generated and assigned from a sequence:

alias :attributes_with_quotes_pre_oracle :attributes_with_quotes
def attributes_with_quotes(*args) #:nodoc:
aq = attributes_with_quotes_pre_oracle(*args)
if connection.class == ConnectionAdapters::JdbcAdapter && (connection.is_a?(JdbcSpec::Oracle) || connection.is_a?(JdbcSpec::Mimer))
aq[self.class.primary_key] = "?" if args.first && aq[self.class.primary_key].nil?
end
aq
end

The code will never add a bind variable when no arguments are supplied to the method "attributes_with_quotes". This is due the fact that in the method attributes_with_quotes, the first argument "include_primary_key" is true by default when no value is passed. Many methods in AR::Base, call this method without supplying arguments and going by default behavior.

The line " aq[self.class.primary_key] = "?" if args.first && aq[self.class.primary_key].nil?
" should be modified as follows to make this work:

aq[self.class.primary_key] = "?" if (args.size == 0 || args.first) && aq[self.class.primary_key].nil?

The above code assumes the first argument to be true by default.

Hope this helps.

You can check out the ARJDBC trunk from

http://jruby-extras.rubyforge.org/svn/trunk/activerecord-jdbc

And run the rake on top of JRuby 1.1 RC1 to build.

You can just copy the dir http://jruby-extras.rubyforge.org/svn/trunk/activerecord-jdbc/lib and update the corresponding lib dir inside your gem install.