[EiresJason]

You need to format the message first so you can input the values into the string and then send the string.

pawn Код:

public OnPlayerDeath(playerid, killerid, reason)
{
        new Float:X,
            Float:Y,
            Float:Z,
            string[60];
        GetPlayerPos(playerid,X,Y,Z);
        format(string,sizeof(string),"Un tizio и morto a %f %f &f!", X, Y, Z);
        SendClientMessage(playerid,0xFFFFFF,string);
        return 1;
}