Possibility to choose private message option for moderator side only too.

It would be nice to be able to set the private discussion option to be seen only from moderator as an option too.
In my easydiscuss i don't want users to have private posting but when i decide as administrator to hide something from public view to be able to hide it by making it private. This option is due some post may have inappropriate content (sexuality or socking) we are a medical site for reproduction and words like vagina are often used....google adsense policy filters can not understand that is a medical question so they see it as policy violation and this causes issues too us. thats all.