Help Converting Please

[Jelf]

Hi all, been trying to convert a script and am stuck with this part,
It returns the error

attempt to call method `CheckIP' (a nil value)

Script cut just for help purpose..

["geoipinfo"] = function(curUser,data)
		local _,_,sip = string.find(data,"^%b<>%s+%+%S+%s+(%d+%.%d+%.%d+%.%d+)")
		if sip then
			-- Check GeoIP
			local ip1,ip2,ipcountry,ipcountrycode = "N/A","N/A","N/A","N/A"
			local ret = GeoIPRange:CheckIP(sip)
			if ret then
				ip1 = DeComputeIP(ret[1])
				ip2 = DeComputeIP(ret[2])
				ipcountry = ret[3]["C"]
				ipcountrycode = ret[3]["CC"]
			end
			SendToUser(curUser,"IP: "..sip..", From: "..ipcountry.." ("..ipcountrycode.."), Range: "..ip1.."-"..ip2,SecuLite.Bot)
		else
			SendToUser(curUser,"Syntax: "..SecuLite.Prefix.."geoipinfo ",SecuLite.Bot)
		end
	end,		
}
function CheckIP(self,ip)
	local cip = ComputeIP(ip)
	local iStart,iEnd,iMid = 1,self:Getn(),0
	while (iStart <= iEnd) do
		iMid = math.floor((iStart+iEnd)/2)
		local table = self:GetIndex(iMid)
		if (table[1] <= cip) and (table[2] >= cip) then
			return table
		elseif (table[1] > cip) then
			iEnd = iMid - 1
		elseif (table[1] < cip) then
			iStart = iMid + 1
		end
	end
end

I know that GeoIPRange is loaded so it must be something to do with how its trying to read the table
Any help appreciated, thanks