This is an odd question. I instantly recognized 40358 as the "hundred-year format" date used by Infinium software on the AS400. I ran 40358 against the converter and returned 6/30/2010. Why would the two platforms differ by one day?

I agree with others that 40358 is odd to have in the question and why would anyone use it instead of a real date if they don't have to. I'm forced to deal with it in the Infinium software but I wouldn't choose to.