[RageCraftLV]

Код:

pName(playerid)
{
    new name[MAX_PLAYER_NAME];
    GetPlayerName(playerid, name);
    return name;
}

public OnPlayerText(playerid, text[])
{
    new string[128];    
    format(string, sizeof string, "[%d] %s: %s", playerid, pName(playerid), text);
    SendClientMessageToAll(-1, string);
    return 0;
}

Haven't tested it, but it should work.

You wanted it to show the ID when player writes something, right?