ActionMailer stopped working after upgrade to Rails 1.1

Hello,

I am using implicit e-mail templates to send HTML messages. I had no
problems till I have upgraded to Rails 1.1. Now the deliver_xxx method
just fails without any error message. No error or whatsoever (both
in development and production environments) exist in logs. Stranger
than that, a blank page is being displayed (according to logs, 0
length response, with 200 OK code). I googled for hours without any
success. What am I doing wrong? To repeat, the code works perfectly
with Rails 1.0.

Snippets from my code:

app/models/mailer.rb:

def contact_us(options)
recipients options[:recipients] || $site_email
subject options[:subject] || $site_name + ’ - Web S.
Inquiry’
from options[:from] || $site_email
body options[:body] || {}
end

app/controllers/sections_controller.rb:
Mailer::deliver_contact_us(
:body => {
:name => @contact_form.user,
:email => @contact_form.email,
:message => @contact_form.message
},
:from => @contact_form.email
)

app/views/mailer/contact_us.text.html.rhtml:

./script/about output:

About your application’s environment
Ruby version 1.8.4 (i486-linux)
RubyGems version 0.8.11
Rails version 1.1.2
Active Record version 1.14.2
Action Pack version 1.12.1
Action Web Service version 1.1.2
Action Mailer version 1.2.1
Active Support version 1.3.1
Application root /home/umit/web/aaa-bbb.com
Environment development
Database adapter postgresql
Database schema version 2

This box runs Ubuntu Breezy on an i386.

Any help is appreciated.

Regards,
Umit Oztosun