Lync 2010 Group Conversation - 60+ ppl

Hello

I was wondering if anyone has experienced the below behavior before in Lync 2010:

I have a user who has a personal contact list group in their Lync 2010 client with over 60+ people. If this user right clicks on the group and starts a group IM conversation, the first message she sends is visible to the participants in the notification toast but once they into the actual conversation the first message isn't there. My thought is that it has to do with the fact that she is inviting so many people at once to a group conversation.

Any ideas?

Thanks,