[Biesmen]

You can make your own system, but it will give the warning "Server closed connection" anyway.

Here's a method how to make your own IP ban system.
Create a table "ipbans", within that table create a field "ip", varchar 16 characters.
Then create a command, e.g /banip [playerid/PartOfName] (using ZCMD):

pawn Code:

CMD:banip(playerid, params[])
{
    new query[128], giveplayerid, IP[16];
    if(IsPlayerAdmin(playerid)) // Checks if the player is a RCON admin
    {
        if(sscanf(params, "u", giveplayerid)) return SendClientMessage(playerid, -1, "Usage: /ban [Playerid/PartOfName]");
        if(!IsPlayerConnected(giveplayerid)) return SendClientMessage(playerid, -1, "This player is not connected.");
        GetPlayerIp(giveplayerid, IP, sizeof(IP));
        format(query, sizeof(query), "INSERT INTO `ipbans` (`ip`) VALUES ('%s')", IP);
        mysql_query(query);
        SendClientMessage(giveplayerid, -1, "You are banned, bai.");
        Kick(giveplayerid);
    }
    else
    {
        SendClientMessage(playerid, -1, "You are not an admin");
    }
    return 1;
}

Somewhere in your script:

pawn Code:

stock IsPlayerBanned(playerid)
{
    new query[128], ip[16];
    GetPlayerIp(playerid, ip, sizeof(ip));
    format(query, sizeof(query), "SELECT * FROM `ipbans` WHERE `ip` = '%s'", ip);
    mysql_query(query);
    mysql_store_result();
    if(mysql_num_rows() == 0)
    {
        return 0; // He's not banned
    }
    mysql_free_result();
    return 1; // Yes he's banned
}

At OnPlayerConnect:

pawn Code:

if(IsPlayerBanned(playerid))
{
    SendClientMessage(playerid, -1, "You're banned, bai bai");
    Kick(playerid);
    return 1;
}

I recommend you to use the normal Ban(playerid); function though.
Good luck