Smail rewrite From address

[Steve George <steve@blah.dircon.co.uk>]

Hi,

I currently use a Debian machine as my main machine at work but am having a 
problem with mail.  The problem is that I need the from address to be 
steveg@domain .com but smail keeps making the From address 
steve@subdomain.domain.com.  Because we have a firewall (and for some other 
weird reasons) I am not allowed to use th subdomain part.  So is there any
way I can rewrite the From address on all outoing mail (or just the stuff from
my account) so that it is steveg@domain.com.

Any pointers to info along these lines would be great - atm I've had to giveup
mutt for Netscape mailer :-(

Thanks,

Steve