[ball]

Код:

public OnPlayerEnterVehicle(playerid, vehicleid, ispassenger)
{
	if(ispassenger)
	{
		if(!IsVehicleOccupied(vehicleid))
		{
    			SendClientMessage(playerid, COLOR_RED, "Don't enter a vehicle without driver.");
    			return ClearAnimations(playerid);
		}
	}
	return 1;
}

ClearAnimations is better solution, don't need to get/set player position.