[rt-users] no outgoing email from RT3

[Craig Askings]

Hi there,

Could sombody please help me with this problem. My RT installation 
doesn't generate any outgoing email.
Whenever I send an email to my RT installation is is processed and is 
entered into the queue. However it doesn't autoreply and I get the 
following in my logs.

Dec 12 15:49:14 epsilon3 RT: 
<rt-3.0.7_01-5-11.4.80810978777889 at askings.com.au> #5/11 - Scrip 2  
(/usr/share/perl5/RT/Action/SendEmail.pm:92)
Dec 12 15:49:14 epsilon3 RT: RT::Scrip=HASH(0x9821e4c): Couldn't commit 
Autoreply To Requestors (/usr/share/perl5/RT/Scrip_Overlay.pm:353)

and when I respond to a ticket the following appears in my logs.

Dec 12 15:54:43 epsilon3 RT: 
<rt-3.0.7_01-3-12.10.11237058395 at askings.com.au> #3/12 - Scrip 9  
(/usr/share/perl5/RT/Action/SendEmail.pm:92)
Dec 12 15:54:43 epsilon3 RT: RT::Scrip=HASH(0x958b7ac): Couldn't commit 
Notify Requestors (/usr/share/perl5/RT/Scrip_Overlay.pm:353)

exim4 is my smtp server and this is how I have the relevent sections in 
RT_SiteConfig.pm

Set($MailCommand , 'sendmail');
Set($SendmailArguments , "-oi ");

Any ideas on why this isn't working?

Regards,
Craig Askings.