[Help] How to pass multiple arguments to a method in a worker?

Hi, guys,
I ran into a problem while I tried to pass more than one parameters to a method in the worker class, it fails, from the backgroundrb log, I found that:

  You have a nil object when you didn't expect it!
  You might have expected an instance of ActiveRecord::Base.
  The error occurred while evaluating nil.[]

Seems the args is nil, but a hash I passed in my controller. From the post: http://rubyforge.org/pipermail/backgroundrb-devel/2008-April/001668.html, it should be a hash if there are multiple arguments. Here's what I did:

In my controller:
def blah
  MiddleMan.worker(:hard_worker).send_mail(:args => {:recipient => 'blahblah@gmail.com', :subject => 'BlahBlah'})

In my worker class:
def send_mail(args)
  emailer.send_mail(args[:recipient], args[:subject])

Is there anything wrong?

Additional info:
backgroundrb 1.0.4

All the best,
Hao Liu

Hao Liu wrote:

  MiddleMan.worker(:hard_worker).send_mail(:args => {:recipient =>
'blahblah@gmail.com', :subject => 'BlahBlah'})

Just send the parameters as a single hash:

send_mail(:recipient => 'blah@blah.org', :subject => 'BlahBlah')