[Fj0rtizFredde]

You need to get the player name too.

pawn Code:

public OnPlayerText(playerid,text[])
{
    new str[128], pName[MAX_PLAYER_NAME];
    GetPlayerName(playerid, pName, sizeof(pName));
    format(str, sizeof(str), "[ID:%i] %s: %s", playerid, pName, text);
    SendPlayerMessageToAll(playerid,str);
    return 0;
}