How do I change the address the mail is sent from for email notifications?

[Menard, Chris]

if using mailx, the -R parm sets the 'return' address.

echo "message" | mailx -s subject -R nagios_from_address at nagios_server to_address at domain.com
________________________________________
From: Esteban Torres Rodriguez [etorres at dap.es]
Sent: Monday, September 07, 2009 2:56 AM
To: nagios-user Mailinglist
Subject: [Nagios-users] How do I change the address the mail is sent from       for email notifications?

I'm trying to do this but I do not work.

http://support.nagios.com/knowledgebase/faqs/index.php?option=com_content&view=article&id=52&catid=35&faq_id=338&expand=false&showdesc=true

Does anyone help me?
I've tried to do with mailx but does not work either.

--
##################################################
# Esteban Torres Rodríguez                       #
# Área de Soporte Técnico                        #
# Subdirección de Sistemas Informáticos          #
# Empresa Pública Desarrollo Agrario y Pesquero  #
# email: etorres at dap.es                          #
##################################################


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Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day 
trial. Simplify your report design, integration and deployment - and focus on 
what you do best, core application coding. Discover what's new with 
Crystal Reports now.  http://p.sf.net/sfu/bobj-july
_______________________________________________
Nagios-users mailing list
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::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. 
::: Messages without supporting info will risk being sent to /dev/null