KMail - Hiding the 'To:' address in a distribution list

With other email clients I have used in the past, I can setup a distribution 
list, and there is a setting to hide all the 'To' addresses. In fact, in 
Pegasus, I think you just fill in your own email address as the 'To' for the 
distribution list, and then simply send the email to the distribution list.

All recipients (all those addresses in the distribution list) receive a copy 
of the email, but their email address acts like a BCC , it can't be seen by 
others.

I have setup a small distribution list in KMail to test, but it doesn't seem 
to have a feature to 'hide' the recipients when the email is sent.

Also, the editor for the distribution list is not real user friendly, to add 
another email address in the list, there is no function to simply add the 
address to the other addresses (all in the one box, that is).

I have Googled a bit, and looked on the KMail website, but there seems no 
documentation for distribution lists.

Have tried 'Help  |  KMail handbook" and get 'The file or folder 
help:/kmail/index.html does not exist.'

Using  ..

KMail
Version 1.10.3
Using KDE 4.1.3 (KDE 4.1.3)

Peter