It'll get sent as a message like if you would simply typed it. You can't really "fake" the name above the message. However, you
may use the following code to temporary change your name.
code:
var sOriginalName = Messenger.MyName; //Save your name
Messenger.MyName = Contact.Name; //Set your name to the contact's name
//Do the stuff
var newChatWnd = Messenger.OpenChat("bla2@bla2.com");
newChatWnd.SendMessage(Message);
Messenger.MyName = sOriginalName; //Reset your name
However, I don't encourage the use of such methods.
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