InfinityScript - Replace Chat Messages

[Okitashi]

Hello there
currently i try to code a Plugin for MW3 with InfinityScript.

I wanna replace the message, whitch the player types.

my code:

 string prefix = "^1";
            string orimsg = message.ToString();

            string new1 = prefix + orimsg;
            Utilities.RawSayAll(new1);

the result is that it will print out 2 messages into the game chat.
Any help?