Creating Lync Meeting with an announcement before anyone join

Hello Everyone,

I would like to know if there's a possibility to add this feature to Lync Meetings. I would like to add an announcement for every party that joins a meeting.

"The announcement/voice message will say to every individual that joins the meeting to not talk until he's allowed."

if not, then is there away to show a message in the meeting window it self? I found there's a message part in Lync web scheduler but i'm not sure where does it show?

thanks

Mohammed JH